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Multiply by a one-digit number

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5160524
Find \(18 \times 6\) in two different ways. Method 1: Break \(18\) into \(10 + 8\). Method 2: Start with \(20 \times 6\), and then subtract the extra amount.

Hints

- Use the distributive property to break a factor into easier parts. - When you begin with a factor that is too large, subtract the product for the extra part. - How much greater is \(20\) than \(18\)?

Solution

1. Method 1: Use the distributive property. \(10 \times 6 = 60\) and \(8 \times 6 = 48\). Then \(60 + 48 = 108\). 2. Method 2: Use a nearby multiple of ten. \(20 \times 6 = 120\). The extra amount is \(2 \times 6 = 12\), so \(120 - 12 = 108\).

Answer

Method 1: \(10 \times 6 + 8 \times 6 = 60 + 48 = 108\) Method 2: \(20 \times 6 - 2 \times 6 = 120 - 12 = 108\)
5161244
Find four times each number. Use an efficient mental or written strategy. a) \(325\) b) \(550\) c) \(825\) d) \(1400\) e) \(2350\)

Hints

- What happens if you double a number and then double the result? - Can you break the number into thousands, hundreds, tens, and ones? - Is there a nearby number that makes the multiplication easier?

Solution

Four times a number can be found by doubling twice or by breaking the number apart by place value. 1. \(325 \times 4 = 1300\), because \(325 \times 2 = 650\) and \(650 \times 2 = 1300\). 2. \(550 \times 4 = 2200\), because \(500 \times 4 = 2000\) and \(50 \times 4 = 200\). 3. \(825 \times 4 = 3300\), because \(800 \times 4 = 3200\) and \(25 \times 4 = 100\). 4. \(1400 \times 4 = 5600\), because \(14 \times 4 = 56\) and the product is \(100\) times as large. 5. \(2350 \times 4 = 9400\), because \(2000 \times 4 = 8000\) and \(350 \times 4 = 1400\).

Answer

a) \(1300\) b) \(2200\) c) \(3300\) d) \(5600\) e) \(9400\)
5161254
Each value below is half of a number. Find the whole number. a) \(175\) b) \(430\) c) \(615\) d) \(840\) e) \(1350\)

Hints

- How can you find a whole when you know one half? - Which operation reverses halving? - Break each value into parts that are easy to double.

Solution

To find the whole number from its half, multiply by \(2\), or double the given value. 1. \(175 \times 2 = 350\). 2. \(430 \times 2 = 860\). 3. \(615 \times 2 = 1230\). 4. \(840 \times 2 = 1680\). 5. \(1350 \times 2 = 2700\).

Answer

a) \(350\) b) \(860\) c) \(1230\) d) \(1680\) e) \(2700\)
5166914
Break \(7 \times 364\) into partial products. 1. Find \(7 \times 300\), \(7 \times 60\), and \(7 \times 4\). 2. Use the partial products to find \(7 \times 364\). 3. Use the needed partial products to find \(7 \times 304\).

Hints

- Break the three-digit factor into hundreds, tens, and ones. - Use \(7 \times 3\) to help find \(7 \times 300\). - Which partial product is not needed for \(7 \times 304\)?

Solution

1. The partial products are \(7 \times 300 = 2100\), \(7 \times 60 = 420\), and \(7 \times 4 = 28\). 2. Add all three partial products: \(2100 + 420 + 28 = 2548\). Therefore, \(7 \times 364 = 2548\). 3. For \(7 \times 304\), use only the hundreds and ones partial products: \(2100 + 28 = 2128\).

Answer

1. Partial products: \(2100\), \(420\), \(28\) 2. \(7 \times 364 = 2548\) 3. \(7 \times 304 = 2128\)
5175724
Find the missing numbers. Use each decomposition to make the multiplication easier. a) \(7 \times 9 = (7 \times 10) - (7 \times \square)\) b) \(8 \times 6 = (\square \times 6) + (\square \times 6)\) Use two equal numbers. c) \(4 \times 12 = (4 \times 10) + (4 \times \square)\) d) \(9 \times 8 = (5 \times 8) + (\square \times 8)\)

Hints

- For part a, think of \(9\) as one less than \(10\). - For part b, find two equal addends whose sum is \(8\). - For each part, check that the decomposed factors combine to make the original factor.

Solution

1. Part a: Since \(9 = 10 - 1\), \(7 \times 9 = 7 \times 10 - 7 \times 1\). The missing number is \(1\). 2. Part b: Since \(8 = 4 + 4\), \(8 \times 6 = 4 \times 6 + 4 \times 6\). Both missing numbers are \(4\). 3. Part c: Since \(12 = 10 + 2\), \(4 \times 12 = 4 \times 10 + 4 \times 2\). The missing number is \(2\). 4. Part d: Since \(9 = 5 + 4\), \(9 \times 8 = 5 \times 8 + 4 \times 8\). The missing number is \(4\).

Answer

a) \(1\) b) \(4\) and \(4\) c) \(2\) d) \(4\)
5177654
Find each product. For part a, show how you decompose the two-digit factor into tens and ones. a) \(7 \times 13\) b) \(4 \times 24\) c) \(3 \times 28\) d) \(6 \times 15\)

Hints

- Decompose the two-digit factor into tens and ones. - Multiply the one-digit factor by each part. - Add the two partial products.

Solution

1. Decompose \(13\) as \(10 + 3\). Then \(7 \times 10 = 70\) and \(7 \times 3 = 21\). Add the partial products: \(70 + 21 = 91\). 2. Decompose \(24\) as \(20 + 4\). Then \(4 \times 20 = 80\) and \(4 \times 4 = 16\). Add: \(80 + 16 = 96\). 3. Decompose \(28\) as \(20 + 8\). Then \(3 \times 20 = 60\) and \(3 \times 8 = 24\). Add: \(60 + 24 = 84\). 4. Decompose \(15\) as \(10 + 5\). Then \(6 \times 10 = 60\) and \(6 \times 5 = 30\). Add: \(60 + 30 = 90\).

Answer

a) \(91\) b) \(96\) c) \(84\) d) \(90\)
5183004
Find each product by decomposing the multi-digit factor into hundreds, tens, and ones. a) \(130 \times 4\) b) \(210 \times 3\) c) \(125 \times 2\) d) \(112 \times 5\) e) \(241 \times 2\)

Hints

- Decompose the multi-digit factor into hundreds, tens, and ones. - Multiply each place-value part by the one-digit factor. - Add the partial products.

Solution

1. For part a, \(100 \times 4 = 400\) and \(30 \times 4 = 120\). Add the partial products: \(400 + 120 = 520\). 2. For part b, \(200 \times 3 = 600\) and \(10 \times 3 = 30\). Add: \(600 + 30 = 630\). 3. For part c, \(100 \times 2 = 200\), \(20 \times 2 = 40\), and \(5 \times 2 = 10\). Add: \(200 + 40 + 10 = 250\). 4. For part d, \(100 \times 5 = 500\), \(10 \times 5 = 50\), and \(2 \times 5 = 10\). Add: \(500 + 50 + 10 = 560\). 5. For part e, \(200 \times 2 = 400\), \(40 \times 2 = 80\), and \(1 \times 2 = 2\). Add: \(400 + 80 + 2 = 482\).

Answer

a) \(520\) b) \(630\) c) \(250\) d) \(560\) e) \(482\)
5183184
Use the standard algorithm to calculate each product. a) \(4719 \times 3\) b) \(826 \times 8\)

Hints

- Multiply from right to left, one place at a time. - Add each regrouped amount in the next place. - Record regrouped digits above the next place so they are not forgotten.

Solution

1. For a), \(9 \times 3 = 27\), so write \(7\) and regroup \(2\) tens. Then \(1 \times 3 + 2 = 5\). Next, \(7 \times 3 = 21\), so write \(1\) and regroup \(2\) thousands. Finally, \(4 \times 3 + 2 = 14\). Therefore, \(4719 \times 3 = 14{,}157\). 2. For b), \(6 \times 8 = 48\), so write \(8\) and regroup \(4\) tens. Then \(2 \times 8 + 4 = 20\), so write \(0\) and regroup \(2\) hundreds. Finally, \(8 \times 8 + 2 = 66\). Therefore, \(826 \times 8 = 6608\).

Answer

a) \(14{,}157\) b) \(6608\)
5183434
A baker makes \(124\) rolls on a regular day. For a school event, the baker needs to make \(6\) times as many rolls. How many rolls does the baker need to make for the event?

Hints

- Decompose \(124\) into hundreds, tens, and ones. - Multiply each part by \(6\). - Add the partial products.

Solution

1. Multiply \(124\) by \(6\): \(124 \times 6\). 2. Decompose \(124\) by place value: \(124 = 100 + 20 + 4\). 3. Multiply each part: \(100 \times 6 = 600\), \(20 \times 6 = 120\), and \(4 \times 6 = 24\). 4. Add the partial products: \(600 + 120 + 24 = 744\).

Answer

The baker needs to make \(744\) rolls.
5185134
Find four times \(58\). Then find the number that is nine times \(82\).

Hints

- Decompose each two-digit number into tens and ones. - Multiply each part by the one-digit factor. - Add the partial products.

Solution

1. For \(58 \times 4\), decompose \(58\) as \(50 + 8\). Then \(50 \times 4 = 200\) and \(8 \times 4 = 32\). Add: \(200 + 32 = 232\). 2. For \(82 \times 9\), decompose \(82\) as \(80 + 2\). Then \(80 \times 9 = 720\) and \(2 \times 9 = 18\). Add: \(720 + 18 = 738\).

Answer

\(232\) and \(738\)
5187994
One science experiment kit costs \(\$132\). A school buys \(3\) kits. What is the total cost?

Hints

- Multiply the cost of one kit by the number of kits. - Break \(132\) into hundreds, tens, and ones. - Add the partial products.

Solution

1. Multiply the price by the number of kits: \(\$132 \times 3\). 2. Use place value: \(\$100 \times 3 = \$300\), \(\$30 \times 3 = \$90\), and \(\$2 \times 3 = \$6\). 3. Add the partial products: \(\$300 + \$90 + \$6 = \$396\).

Answer

The total cost is \(\$396\).
5188184
A bakery delivers \(135\) rolls to a hotel each day. How many rolls does the bakery deliver in \(7\) days?

Hints

- Multiply the number of rolls delivered each day by \(7\). - Break \(135\) into hundreds, tens, and ones. - Add the partial products.

Solution

1. Multiply the daily amount by the number of days: \(135 \times 7\). 2. Use place value: \(100 \times 7 = 700\), \(30 \times 7 = 210\), and \(5 \times 7 = 35\). 3. Add the partial products: \(700 + 210 + 35 = 945\).

Answer

The bakery delivers \(945\) rolls in \(7\) days.
5191284
Rewrite the repeated addition as a sum of two products, then evaluate it. \(14 + 14 + 14 + 14 + 14 + 22 + 22 + 22 + 22\)

Hints

- Count how many times each addend appears. - Write each repeated addend as a multiplication expression. - Evaluate the products before adding them.

Solution

1. The addend \(14\) appears \(5\) times, and \(22\) appears \(4\) times. 2. Rewrite the expression as \(5 \times 14 + 4 \times 22\). 3. Evaluate the products: \(5 \times 14 = 70\) and \(4 \times 22 = 88\). 4. Add: \(70 + 88 = 158\).

Answer

\(5 \times 14 + 4 \times 22 = 158\)
5192134
An apple farm packs exactly \(8\) apples in each bag. During the morning, workers fill \(435\) bags. How many apples do they pack in all?

Hints

- Equal groups can be represented with multiplication. - Identify the number in each group and the number of groups. - Break \(435\) into hundreds, tens, and ones.

Solution

1. Multiply the number of bags by the number of apples in each bag: \(435 \times 8\). 2. Use place value: \(400 \times 8=3200\), \(30 \times 8=240\), and \(5 \times 8=40\). 3. Add: \(3200+240+40=3480\).

Answer

They pack \(3480\) apples in all.
5193734
Use the standard algorithm to calculate \(4152\times 6\). Then check your product with the related division equation.

Hints

- Division is the inverse operation of multiplication. - Dividing your product by \(6\) should give the other factor. - Check each regrouping step in the multiplication algorithm.

Solution

1. Multiply by place value. Ones: \(2\times 6=12\), so write \(2\) and regroup \(1\) ten. Tens: \(5\times 6+1=31\), so write \(1\) and regroup \(3\) hundreds. Hundreds: \(1\times 6+3=9\). Thousands: \(4\times 6=24\). Therefore, \(4152\times 6=24{,}912\). 2. Use division to check the product: \(24{,}912\div 6=4152\). 3. The quotient equals the original factor, so the product is correct.

Answer

The product is \(24{,}912\). Check: \(24{,}912\div 6=4152\).
5194724
Complete each equation. a) \(130 \times 5 = \square\) b) \(\square \times 3 = 720\) c) \(4 \times \square = 880\) d) \(250 \times 4 = \square\)

Hints

- Use division when a factor is missing. - Use place value and partial products for the multiplication. - Check missing factors by multiplication.

Solution

1. In a), \(130 \times 5 = 650\). 2. In b), \(720 \div 3 = 240\), so \(240 \times 3 = 720\). 3. In c), \(880 \div 4 = 220\), so \(4 \times 220 = 880\). 4. In d), \(250 \times 4 = 1000\).

Answer

a) \(650\) b) \(240\) c) \(220\) d) \(1000\)
5194754
A plant nursery receives \(240\) seedlings in each tray. A gardener buys \(4\) trays. How many seedlings does the gardener have in all?

Hints

- Multiply the number of trays by the number of seedlings in each tray. - Break \(240\) into hundreds and tens. - Add the partial products.

Solution

1. Multiply the number of trays by the number of seedlings in each tray: \(4 \times 240\). 2. Decompose \(240\): \(240 = 200 + 40\). 3. Find the partial products: \(4 \times 200 = 800\) and \(4 \times 40 = 160\). 4. Add: \(800 + 160 = 960\).

Answer

The gardener has \(960\) seedlings in all.
5195014
A printing company packs \(213\) notebooks in each carton. An elementary school orders \(3\) cartons. How many notebooks does the school receive in all?

Hints

- Break \(213\) into hundreds, tens, and ones. - Multiply each part by \(3\). - Add the partial products.

Solution

1. Multiply the number in each carton by the number of cartons: \(213 \times 3\). 2. Decompose \(213\): \(213 = 200 + 10 + 3\). 3. Find the partial products: \(200 \times 3 = 600\), \(10 \times 3 = 30\), and \(3 \times 3 = 9\). 4. Add: \(600 + 30 + 9 = 639\).

Answer

The school receives \(639\) notebooks.
5196294
Use place-value decomposition to calculate each product mentally. Show how you split the two-digit factor. a) \(42 \times 6\) b) \(83 \times 4\)

Hints

- Split the two-digit factor into tens and ones. - Multiply each part by the one-digit factor. - Add the partial products.

Solution

1. For a), decompose \(42\) as \(40 + 2\): \(40 \times 6 + 2 \times 6 = 240 + 12 = 252\). 2. For b), decompose \(83\) as \(80 + 3\): \(80 \times 4 + 3 \times 4 = 320 + 12 = 332\).

Answer

a) \(42 = 40 + 2\), so \(40 \times 6 + 2 \times 6 = 252\). b) \(83 = 80 + 3\), so \(80 \times 4 + 3 \times 4 = 332\).
5198304
Find each product. Break the three-digit factor into hundreds, tens, and ones and use partial products. a) \(213 \times 3\) b) \(124 \times 2\) c) \(402 \times 2\) d) \(310 \times 3\)

Hints

- Break each three-digit factor into hundreds, tens, and ones. - Multiply each part by the one-digit factor. - Add the partial products. - Pay special attention to place values containing zero.

Solution

1. For part a, \(200 \times 3 = 600\), \(10 \times 3 = 30\), and \(3 \times 3 = 9\). Then \(600 + 30 + 9 = 639\). 2. For part b, \(100 \times 2 = 200\), \(20 \times 2 = 40\), and \(4 \times 2 = 8\). Then \(200 + 40 + 8 = 248\). 3. For part c, \(400 \times 2 = 800\), \(0 \times 2 = 0\), and \(2 \times 2 = 4\). Then \(800 + 0 + 4 = 804\). 4. For part d, \(300 \times 3 = 900\), \(10 \times 3 = 30\), and \(0 \times 3 = 0\). Then \(900 + 30 + 0 = 930\).

Answer

a) \(639\) b) \(248\) c) \(804\) d) \(930\)
5198514
Find each product using partial products. a) \(15 \times 6\) b) \(23 \times 4\) c) \(42 \times 8\) d) \(76 \times 3\)

Hints

- Break the two-digit factor into tens and ones. - Multiply each part by the one-digit factor. - Add the two partial products.

Solution

1. For part a, \(10 \times 6 = 60\) and \(5 \times 6 = 30\). Then \(60 + 30 = 90\). 2. For part b, \(20 \times 4 = 80\) and \(3 \times 4 = 12\). Then \(80 + 12 = 92\). 3. For part c, \(40 \times 8 = 320\) and \(2 \times 8 = 16\). Then \(320 + 16 = 336\). 4. For part d, \(70 \times 3 = 210\) and \(6 \times 3 = 18\). Then \(210 + 18 = 228\).

Answer

a) \(90\) b) \(92\) c) \(336\) d) \(228\)
5198584
Find each product using mental math or partial products. a) \(214 \times 3\) b) \(152 \times 4\) c) \(326 \times 2\) d) \(118 \times 5\)

Hints

- Break each three-digit factor into hundreds, tens, and ones. - Multiply each part by the one-digit factor. - Add all three partial products. - Pay attention to zeros in products such as \(50 \times 4\).

Solution

1. For part a, \(200 \times 3 = 600\), \(10 \times 3 = 30\), and \(4 \times 3 = 12\). Then \(600 + 30 + 12 = 642\). 2. For part b, \(100 \times 4 = 400\), \(50 \times 4 = 200\), and \(2 \times 4 = 8\). Then \(400 + 200 + 8 = 608\). 3. For part c, \(300 \times 2 = 600\), \(20 \times 2 = 40\), and \(6 \times 2 = 12\). Then \(600 + 40 + 12 = 652\). 4. For part d, \(100 \times 5 = 500\), \(10 \times 5 = 50\), and \(8 \times 5 = 40\). Then \(500 + 50 + 40 = 590\).

Answer

a) \(642\) b) \(608\) c) \(652\) d) \(590\)
5202064
Find each product. Use any efficient method. a) \(14 \times 7\) b) \(23 \times 4\) c) \(36 \times 2\) d) \(5 \times 18\) e) \(9 \times 12\)

Hints

- Break the two-digit factor into tens and ones. - Multiply each part, then add the partial products. - You may switch the order of the factors when that makes a fact easier.

Solution

1. For part a, \(10 \times 7 = 70\) and \(4 \times 7 = 28\). Then \(70 + 28 = 98\). 2. For part b, \(20 \times 4 = 80\) and \(3 \times 4 = 12\). Then \(80 + 12 = 92\). 3. For part c, \(30 \times 2 = 60\) and \(6 \times 2 = 12\). Then \(60 + 12 = 72\). 4. For part d, \(5 \times 10 = 50\) and \(5 \times 8 = 40\). Then \(50 + 40 = 90\). 5. For part e, \(9 \times 10 = 90\) and \(9 \times 2 = 18\). Then \(90 + 18 = 108\).

Answer

a) \(98\) b) \(92\) c) \(72\) d) \(90\) e) \(108\)
5202124
Find each product using partial products. a) \(103 \times 9\) b) \(105 \times 7\) c) \(108 \times 4\) d) \(106 \times 8\) e) \(104 \times 5\) f) \(107 \times 3\)

Hints

- Break each three-digit factor into hundreds and ones. - Multiply the hundreds part by the one-digit factor. - Multiply the ones part by the one-digit factor. - Add the two partial products.

Solution

1. For part a, \(100 \times 9 = 900\) and \(3 \times 9 = 27\). Then \(900 + 27 = 927\). 2. For part b, \(100 \times 7 = 700\) and \(5 \times 7 = 35\). Then \(700 + 35 = 735\). 3. For part c, \(100 \times 4 = 400\) and \(8 \times 4 = 32\). Then \(400 + 32 = 432\). 4. For part d, \(100 \times 8 = 800\) and \(6 \times 8 = 48\). Then \(800 + 48 = 848\). 5. For part e, \(100 \times 5 = 500\) and \(4 \times 5 = 20\). Then \(500 + 20 = 520\). 6. For part f, \(100 \times 3 = 300\) and \(7 \times 3 = 21\). Then \(300 + 21 = 321\).

Answer

a) \(927\) b) \(735\) c) \(432\) d) \(848\) e) \(520\) f) \(321\)
5202134
Find each product using partial products. a) \(231 \times 3\) b) \(112 \times 7\) c) \(145 \times 2\) d) \(324 \times 2\) e) \(118 \times 5\)

Hints

- Break each three-digit factor into hundreds, tens, and ones. - Find a separate partial product for each place-value part. - Add the partial products. - Watch for regrouping when you add the partial products.

Solution

1. For part a, \(200 \times 3 = 600\), \(30 \times 3 = 90\), and \(1 \times 3 = 3\). Then \(600 + 90 + 3 = 693\). 2. For part b, \(100 \times 7 = 700\), \(10 \times 7 = 70\), and \(2 \times 7 = 14\). Then \(700 + 70 + 14 = 784\). 3. For part c, \(100 \times 2 = 200\), \(40 \times 2 = 80\), and \(5 \times 2 = 10\). Then \(200 + 80 + 10 = 290\). 4. For part d, \(300 \times 2 = 600\), \(20 \times 2 = 40\), and \(4 \times 2 = 8\). Then \(600 + 40 + 8 = 648\). 5. For part e, \(100 \times 5 = 500\), \(10 \times 5 = 50\), and \(8 \times 5 = 40\). Then \(500 + 50 + 40 = 590\).

Answer

a) \(693\) b) \(784\) c) \(290\) d) \(648\) e) \(590\)
5202184
Find each product using partial products. Break the two-digit factor into tens and ones. a) \(13 \times 7\) b) \(16 \times 6\) c) \(14 \times 8\) d) \(12 \times 9\)

Hints

- Break the two-digit factor into tens and ones. - Multiply each part by the one-digit factor. - Add the partial products. - Use basic multiplication facts to check the partial products.

Solution

1. For part a, \(10 \times 7 = 70\) and \(3 \times 7 = 21\). Then \(70 + 21 = 91\). 2. For part b, \(10 \times 6 = 60\) and \(6 \times 6 = 36\). Then \(60 + 36 = 96\). 3. For part c, \(10 \times 8 = 80\) and \(4 \times 8 = 32\). Then \(80 + 32 = 112\). 4. For part d, \(10 \times 9 = 90\) and \(2 \times 9 = 18\). Then \(90 + 18 = 108\).

Answer

a) \(91\) b) \(96\) c) \(112\) d) \(108\)
5202224
Find each product using partial products. a) \(42 \times 4\) b) \(35 \times 3\) c) \(61 \times 5\) d) \(24 \times 8\)

Hints

- Break the two-digit factor into tens and ones. - Find the tens partial product. - Find the ones partial product. - Add the two results.

Solution

1. For part a, \(40 \times 4 = 160\) and \(2 \times 4 = 8\). Then \(160 + 8 = 168\). 2. For part b, \(30 \times 3 = 90\) and \(5 \times 3 = 15\). Then \(90 + 15 = 105\). 3. For part c, \(60 \times 5 = 300\) and \(1 \times 5 = 5\). Then \(300 + 5 = 305\). 4. For part d, \(20 \times 8 = 160\) and \(4 \times 8 = 32\). Then \(160 + 32 = 192\).

Answer

a) \(168\) b) \(105\) c) \(305\) d) \(192\)
5202234
Complete the partial-products work for \(76 \times 4\). \(70 \times 4 = \dots\) \(6 \times 4 = \dots\) \(\dots + \dots = \dots\) The product is \(\dots\).

Hints

- Use the basic fact \(7 \times 4\) and place value to find \(70 \times 4\). - Find the ones partial product. - Add the two partial products.

Solution

1. Multiply the tens: \(70 \times 4 = 280\). 2. Multiply the ones: \(6 \times 4 = 24\). 3. Add the partial products: \(280 + 24 = 304\).

Answer

\(70 \times 4 = 280\) \(6 \times 4 = 24\) \(280 + 24 = 304\) The product is \(304\).
5202324
Find each product using partial products. a) \(116 \times 5\) b) \(234 \times 4\) c) \(142 \times 6\) d) \(327 \times 3\)

Hints

- Break each three-digit factor into hundreds, tens, and ones. - Multiply each part by the one-digit factor. - Add the partial products.

Solution

1. For part a, \(100 \times 5 = 500\), \(10 \times 5 = 50\), and \(6 \times 5 = 30\). Then \(500 + 50 + 30 = 580\). 2. For part b, \(200 \times 4 = 800\), \(30 \times 4 = 120\), and \(4 \times 4 = 16\). Then \(800 + 120 + 16 = 936\). 3. For part c, \(100 \times 6 = 600\), \(40 \times 6 = 240\), and \(2 \times 6 = 12\). Then \(600 + 240 + 12 = 852\). 4. For part d, \(300 \times 3 = 900\), \(20 \times 3 = 60\), and \(7 \times 3 = 21\). Then \(900 + 60 + 21 = 981\).

Answer

a) \(580\) b) \(936\) c) \(852\) d) \(981\)
5202384
Find each product using partial products. Break each three-digit factor into hundreds, tens, and ones, and show the intermediate steps. a) \(243 \times 3\) b) \(162 \times 5\) c) \(304 \times 2\)

Hints

- Break each factor into hundreds, tens, and ones. - Find each partial product. - Remember that a zero in a place contributes a partial product of zero.

Solution

1. For part a, \(200 \times 3 = 600\), \(40 \times 3 = 120\), and \(3 \times 3 = 9\). Then \(600 + 120 + 9 = 729\). 2. For part b, \(100 \times 5 = 500\), \(60 \times 5 = 300\), and \(2 \times 5 = 10\). Then \(500 + 300 + 10 = 810\). 3. For part c, \(300 \times 2 = 600\), \(0 \times 2 = 0\), and \(4 \times 2 = 8\). Then \(600 + 0 + 8 = 608\).

Answer

a) \(729\) b) \(810\) c) \(608\)
5202464
Find each product using partial products. a) \(18 \times 4\) b) \(3 \times 26\) c) \(14 \times 7\) d) \(6 \times 15\) e) \(29 \times 2\) f) \(5 \times 17\)

Hints

- Break the two-digit factor into tens and ones. - Multiply each part by the one-digit factor. - Add the partial products.

Solution

1. For part a, \(10 \times 4 = 40\) and \(8 \times 4 = 32\). Then \(40 + 32 = 72\). 2. For part b, \(3 \times 20 = 60\) and \(3 \times 6 = 18\). Then \(60 + 18 = 78\). 3. For part c, \(10 \times 7 = 70\) and \(4 \times 7 = 28\). Then \(70 + 28 = 98\). 4. For part d, \(6 \times 10 = 60\) and \(6 \times 5 = 30\). Then \(60 + 30 = 90\). 5. For part e, \(20 \times 2 = 40\) and \(9 \times 2 = 18\). Then \(40 + 18 = 58\). 6. For part f, \(5 \times 10 = 50\) and \(5 \times 7 = 35\). Then \(50 + 35 = 85\).

Answer

a) \(72\) b) \(78\) c) \(98\) d) \(90\) e) \(58\) f) \(85\)
5202474
Complete each partial-products calculation. a) \(34 \times 5 = \dots\) Tens: \(30 \times 5 = \dots\) Ones: \(4 \times 5 = \dots\) b) \(6 \times 27 = \dots\) Tens: \(6 \times 20 = \dots\) Ones: \(6 \times 7 = \dots\) c) \(4 \times 48 = \dots\) Tens: \(4 \times 40 = \dots\) Ones: \(4 \times 8 = \dots\)

Hints

- Notice how each two-digit factor is broken into tens and ones. - Find both partial products. - Add the partial products to find the total.

Solution

1. For part a, \(30 \times 5 = 150\) and \(4 \times 5 = 20\). Then \(150 + 20 = 170\). 2. For part b, \(6 \times 20 = 120\) and \(6 \times 7 = 42\). Then \(120 + 42 = 162\). 3. For part c, \(4 \times 40 = 160\) and \(4 \times 8 = 32\). Then \(160 + 32 = 192\).

Answer

a) \(30 \times 5 = 150\), \(4 \times 5 = 20\), and \(34 \times 5 = 170\) b) \(6 \times 20 = 120\), \(6 \times 7 = 42\), and \(6 \times 27 = 162\) c) \(4 \times 40 = 160\), \(4 \times 8 = 32\), and \(4 \times 48 = 192\)
5202544
Use the distributive property and the fact that \(9 = 10 - 1\) to calculate mentally. a) \(19 \times 9\) b) \(34 \times 9\) c) \(48 \times 9\) d) \(72 \times 9\)

Hints

- Replace multiplication by \(9\) with multiplication by a nearby number. - Determine how much must be subtracted after multiplying by \(10\). - Apply the same strategy to each factor.

Solution

1. Use \(n \times 9 = n \times 10 - n\). 2. Part a: \(19 \times 9 = 190 - 19 = 171\). 3. Part b: \(34 \times 9 = 340 - 34 = 306\). 4. Part c: \(48 \times 9 = 480 - 48 = 432\). 5. Part d: \(72 \times 9 = 720 - 72 = 648\).

Answer

a) \(171\) b) \(306\) c) \(432\) d) \(648\)
5202624
Find each product. Use the relationships among the problems. a) \(200 \times 4 = \dots\) b) \(30 \times 4 = \dots\) c) \(230 \times 4 = \dots\) d) \(300 \times 3 = \dots\) e) \(7 \times 3 = \dots\) f) \(307 \times 3 = \dots\)

Hints

- Look at the first two problems in each group. - Notice how their factors combine to make the factor in the third problem. - Add the related partial products.

Solution

1. For parts a and b, \(200 \times 4 = 800\) and \(30 \times 4 = 120\). 2. Since \(230 = 200 + 30\), \(230 \times 4 = 800 + 120 = 920\). 3. For parts d and e, \(300 \times 3 = 900\) and \(7 \times 3 = 21\). 4. Since \(307 = 300 + 7\), \(307 \times 3 = 900 + 21 = 921\).

Answer

a) \(800\) b) \(120\) c) \(920\) d) \(900\) e) \(21\) f) \(921\)
5202634
Find each product using partial products. Break the three-digit factor into hundreds, tens, and ones. a) \(212 \times 4\) b) \(135 \times 2\) c) \(306 \times 3\) d) \(150 \times 5\)

Hints

- Break each three-digit factor into place-value parts. - Multiply each part by the one-digit factor. - Add all partial products. - When a place has a zero digit, include its zero partial product correctly.

Solution

1. For part a, \(200 \times 4 = 800\), \(10 \times 4 = 40\), and \(2 \times 4 = 8\). Then \(800 + 40 + 8 = 848\). 2. For part b, \(100 \times 2 = 200\), \(30 \times 2 = 60\), and \(5 \times 2 = 10\). Then \(200 + 60 + 10 = 270\). 3. For part c, \(300 \times 3 = 900\), \(0 \times 3 = 0\), and \(6 \times 3 = 18\). Then \(900 + 0 + 18 = 918\). 4. For part d, \(100 \times 5 = 500\), \(50 \times 5 = 250\), and \(0 \times 5 = 0\). Then \(500 + 250 + 0 = 750\).

Answer

a) \(848\) b) \(270\) c) \(918\) d) \(750\)
5202684
Find each product. Break the two-digit factor into tens and ones. a) \(43 \times 4\) b) \(68 \times 3\) c) \(52 \times 6\) d) \(91 \times 7\) e) \(35 \times 8\)

Hints

- Break the two-digit factor into tens and ones. - Multiply each part by the one-digit factor. - Add the two partial products.

Solution

1. For part a, \(40 \times 4 = 160\) and \(3 \times 4 = 12\). Then \(160 + 12 = 172\). 2. For part b, \(60 \times 3 = 180\) and \(8 \times 3 = 24\). Then \(180 + 24 = 204\). 3. For part c, \(50 \times 6 = 300\) and \(2 \times 6 = 12\). Then \(300 + 12 = 312\). 4. For part d, \(90 \times 7 = 630\) and \(1 \times 7 = 7\). Then \(630 + 7 = 637\). 5. For part e, \(30 \times 8 = 240\) and \(5 \times 8 = 40\). Then \(240 + 40 = 280\).

Answer

a) \(172\) b) \(204\) c) \(312\) d) \(637\) e) \(280\)
5202724
Find each product using partial products. Break the two-digit factor into tens and ones. a) \(14 \times 6\) b) \(17 \times 4\) c) \(23 \times 5\) d) \(32 \times 8\)

Hints

- Break the two-digit factor into tens and ones. - Multiply each part by the one-digit factor. - Add the partial products.

Solution

1. For part a, \(10 \times 6 = 60\) and \(4 \times 6 = 24\). Then \(60 + 24 = 84\). 2. For part b, \(10 \times 4 = 40\) and \(7 \times 4 = 28\). Then \(40 + 28 = 68\). 3. For part c, \(20 \times 5 = 100\) and \(3 \times 5 = 15\). Then \(100 + 15 = 115\). 4. For part d, \(30 \times 8 = 240\) and \(2 \times 8 = 16\). Then \(240 + 16 = 256\).

Answer

a) \(84\) b) \(68\) c) \(115\) d) \(256\)
5202804
Multiply each number by \(4\). Use partial products. a) \(125\) b) \(212\) c) \(180\)

Hints

- Break each three-digit number into hundreds, tens, and ones. - Multiply each part by \(4\). - Add the partial products.

Solution

1. For \(125 \times 4\), the partial products are \(100 \times 4 = 400\), \(20 \times 4 = 80\), and \(5 \times 4 = 20\). Then \(400 + 80 + 20 = 500\). 2. For \(212 \times 4\), the partial products are \(200 \times 4 = 800\), \(10 \times 4 = 40\), and \(2 \times 4 = 8\). Then \(800 + 40 + 8 = 848\). 3. For \(180 \times 4\), the partial products are \(100 \times 4 = 400\) and \(80 \times 4 = 320\). Then \(400 + 320 = 720\).

Answer

a) \(500\) b) \(848\) c) \(720\)
5203884
Use multiplication by \(10\) to calculate each product efficiently. a) \(9 \times 7\) b) \(11 \times 6\) c) \(9 \times 12\)

Hints

- Rewrite \(9\) as \(10 - 1\). - Rewrite \(11\) as \(10 + 1\). - Multiply by \(10\), then adjust by one more group.

Solution

1. For a), use \(10 \times 7 - 1 \times 7 = 70 - 7 = 63\). 2. For b), use \(10 \times 6 + 1 \times 6 = 60 + 6 = 66\). 3. For c), use \(10 \times 12 - 1 \times 12 = 120 - 12 = 108\).

Answer

a) \(63\) b) \(66\) c) \(108\)
5205414
Leon evaluates \(15 \times 4\). Mia evaluates the commutative expression \(4 \times 15\). a) Who gets the greater product? Explain without calculating. b) Use partial products to find the product of both expressions.

Hints

- What happens to a product when the factors switch places? - Break \(15\) into tens and ones. - Multiply each part by \(4\), then add the partial products.

Solution

1. By the commutative property, switching the factors does not change the product, so neither product is greater. 2. Decompose \(15\) into \(10 + 5\): \(15 \times 4 = 10 \times 4 + 5 \times 4 = 40 + 20 = 60\). 3. Therefore, both \(15 \times 4\) and \(4 \times 15\) equal \(60\).

Answer

a) The products are equal because the factors are switched. b) \(15 \times 4 = 10 \times 4 + 5 \times 4 = 60\), so both products are \(60\).
5208984
Find each product. a) \(40 \times 5\) b) \(8 \times 30\) c) \(70 \times 4\) d) \(6 \times 90\) e) \(120 \times 3\) f) \(2 \times 450\) g) \(150 \times 4\) h) \(5 \times 110\)

Hints

- First solve the related basic fact without the trailing zero. - Use place value for multiples of \(10\). - Break a three-digit factor into hundreds and tens when helpful. - Check the number of zeros in each factor and product.

Solution

1. a) \(40 \times 5 = 200\), using the fact \(4 \times 5 = 20\) and place value. 2. b) \(8 \times 30 = 240\), using the fact \(8 \times 3 = 24\) and place value. 3. c) \(70 \times 4 = 280\). 4. d) \(6 \times 90 = 540\). 5. e) \(120 \times 3 = 360\). 6. f) \(2 \times 450 = 900\). 7. g) \(150 \times 4 = 600\). 8. h) \(5 \times 110 = 550\).

Answer

a) \(200\) b) \(240\) c) \(280\) d) \(540\) e) \(360\) f) \(900\) g) \(600\) h) \(550\)
5208994
Find each missing number. a) \(4 \times 80 = \square\) b) \(60 \times \square = 420\) c) \(\square \times 9 = 270\) d) \(230 \times 4 = \square\) e) \(5 \times \square = 450\) f) \(\square \times 7 = 350\)

Hints

- Relate each equation to a basic multiplication fact. - Use place value to explain factors that are ten times as great. - Use the inverse operation for an unknown factor. - Decompose \(230\) into hundreds and tens.

Solution

1. a) \(4 \times 80 = 320\). 2. b) Use the related fact \(6 \times 7 = 42\), so \(60 \times 7 = 420\). 3. c) Use \(3 \times 9 = 27\), so \(30 \times 9 = 270\). 4. d) Decompose \(230\): \(200 \times 4 = 800\) and \(30 \times 4 = 120\). Then \(800 + 120 = 920\). 5. e) Use \(5 \times 9 = 45\), so \(5 \times 90 = 450\). 6. f) Use \(5 \times 7 = 35\), so \(50 \times 7 = 350\).

Answer

a) \(320\) b) \(7\) c) \(30\) d) \(920\) e) \(90\) f) \(50\)
5209074
Find each product using partial products. a) \(105 \times 8\) b) \(203 \times 4\) c) \(170 \times 5\) d) \(120 \times 7\)

Hints

- Break each three-digit factor into hundreds, tens, and ones. - Multiply each nonzero part by the one-digit factor. - Add the partial products. - Pay special attention to any zero place value.

Solution

1. For part a, \(100 \times 8 = 800\) and \(5 \times 8 = 40\). Then \(800 + 40 = 840\). 2. For part b, \(200 \times 4 = 800\) and \(3 \times 4 = 12\). Then \(800 + 12 = 812\). 3. For part c, \(100 \times 5 = 500\) and \(70 \times 5 = 350\). Then \(500 + 350 = 850\). 4. For part d, \(100 \times 7 = 700\) and \(20 \times 7 = 140\). Then \(700 + 140 = 840\).

Answer

a) \(840\) b) \(812\) c) \(850\) d) \(840\)
5209184
Find each product using partial products. a) \(57 \times 4\) b) \(6 \times 83\) c) \(39 \times 8\) d) \(7 \times 92\)

Hints

- Break the two-digit factor into tens and ones. - Multiply the tens part by the one-digit factor. - Multiply the ones part by the one-digit factor. - Add the partial products.

Solution

1. For part a, \(50 \times 4 = 200\) and \(7 \times 4 = 28\). Then \(200 + 28 = 228\). 2. For part b, \(6 \times 80 = 480\) and \(6 \times 3 = 18\). Then \(480 + 18 = 498\). 3. For part c, \(30 \times 8 = 240\) and \(9 \times 8 = 72\). Then \(240 + 72 = 312\). 4. For part d, \(7 \times 90 = 630\) and \(7 \times 2 = 14\). Then \(630 + 14 = 644\).

Answer

a) \(228\) b) \(498\) c) \(312\) d) \(644\)
5209224
Multiply \(60\), \(80\), \(110\), and \(120\) by \(4\). Then multiply the same numbers by \(8\). Compare the two sets of products. What do you notice?

Hints

- Compare the factors \(4\) and \(8\). - Use each product with \(4\) to help find the corresponding product with \(8\). - Check one pair of products first.

Solution

1. Multiplying by \(4\) gives \(60 \times 4 = 240\), \(80 \times 4 = 320\), \(110 \times 4 = 440\), and \(120 \times 4 = 480\). 2. Multiplying by \(8\) gives \(60 \times 8 = 480\), \(80 \times 8 = 640\), \(110 \times 8 = 880\), and \(120 \times 8 = 960\). 3. Since \(8\) is twice \(4\), each product with \(8\) is twice the corresponding product with \(4\).

Answer

Products with \(4\): \(240\), \(320\), \(440\), \(480\) Products with \(8\): \(480\), \(640\), \(880\), \(960\) Each product with \(8\) is twice the matching product with \(4\).
5209234
Find each product using partial products. a) \(140 \times 6\) b) \(125 \times 4\) c) \(230 \times 3\) d) \(112 \times 8\)

Hints

- Break each three-digit factor into place-value parts. - Multiply each part by the one-digit factor. - Add the partial products.

Solution

1. For part a, \(100 \times 6 = 600\) and \(40 \times 6 = 240\). Then \(600 + 240 = 840\). 2. For part b, \(100 \times 4 = 400\), \(20 \times 4 = 80\), and \(5 \times 4 = 20\). Then \(400 + 80 + 20 = 500\). 3. For part c, \(200 \times 3 = 600\) and \(30 \times 3 = 90\). Then \(600 + 90 = 690\). 4. For part d, \(100 \times 8 = 800\), \(10 \times 8 = 80\), and \(2 \times 8 = 16\). Then \(800 + 80 + 16 = 896\).

Answer

a) \(840\) b) \(500\) c) \(690\) d) \(896\)
5209664
Find each product. a) \(145 \times 4\) b) \(86 \times 7\) c) \(213 \times 4\)

Hints

- The product is the result of multiplication. - Break a factor into hundreds, tens, and ones if helpful. - Find and add the partial products.

Solution

1. \(145 \times 4 = 580\). 2. \(86 \times 7 = 602\). 3. \(213 \times 4 = 852\).

Answer

a) \(580\) b) \(602\) c) \(852\)
5210374
Find each product using partial products. Break the two-digit factor into tens and ones. a) \(68 \times 4\) b) \(37 \times 9\) c) \(82 \times 6\) d) \(5 \times 94\)

Hints

- Break the two-digit factor into tens and ones. - Multiply both parts by the one-digit factor. - Add the partial products. - Check for regrouping when adding the two results.

Solution

1. For part a, \(60 \times 4 = 240\) and \(8 \times 4 = 32\). Then \(240 + 32 = 272\). 2. For part b, \(30 \times 9 = 270\) and \(7 \times 9 = 63\). Then \(270 + 63 = 333\). 3. For part c, \(80 \times 6 = 480\) and \(2 \times 6 = 12\). Then \(480 + 12 = 492\). 4. For part d, \(5 \times 90 = 450\) and \(5 \times 4 = 20\). Then \(450 + 20 = 470\).

Answer

a) \(272\) b) \(333\) c) \(492\) d) \(470\)
5210424
Find each product. a) \(150 \times 3\) b) \(4 \times 120\) c) \(230 \times 2\) d) \(70 \times 6\) e) \(9 \times 80\)

Hints

- Break a multi-digit factor into hundreds and tens. - Use the distributive property to multiply each part. - For a multiple of \(10\), use a related basic fact and place value.

Solution

1. \(150 \times 3 = (100 \times 3) + (50 \times 3) = 300 + 150 = 450\). 2. \(4 \times 120 = (4 \times 100) + (4 \times 20) = 400 + 80 = 480\). 3. \(230 \times 2 = (200 \times 2) + (30 \times 2) = 400 + 60 = 460\). 4. \(70 \times 6 = (7 \times 6) \times 10 = 42 \times 10 = 420\). 5. \(9 \times 80 = (9 \times 8) \times 10 = 72 \times 10 = 720\).

Answer

a) \(450\) b) \(480\) c) \(460\) d) \(420\) e) \(720\)
5210454
1. Fill in the missing numbers in the partial-products work for \(136 \times 5\). \(100 \times 5 = \dots\) \(\dots \times 5 = 150\) \(6 \times 5 = \dots\) Product: \(\dots\) 2. Find \(154 \times 4\) using your own partial-products method.

Hints

- Identify the hundreds, tens, and ones in \(136\). - Multiply each place-value part by the one-digit factor. - Add the partial products.

Solution

1. For \(136 \times 5\), \(100 \times 5 = 500\), \(30 \times 5 = 150\), and \(6 \times 5 = 30\). Then \(500 + 150 + 30 = 680\). 2. For \(154 \times 4\), \(100 \times 4 = 400\), \(50 \times 4 = 200\), and \(4 \times 4 = 16\). Then \(400 + 200 + 16 = 616\).

Answer

1. \(100 \times 5 = 500\), \(30 \times 5 = 150\), \(6 \times 5 = 30\), and the product is \(680\). 2. \(154 \times 4 = 616\)
5210474
Complete the table by doubling each number step by step. <table> <tr> <th>Number</th> <th>Double \((\times 2)\)</th> <th>Four times as much \((\times 4)\)</th> <th>Eight times as much \((\times 8)\)</th> </tr> <tr> <td>\(40\)</td><td>\(\dots\)</td><td>\(\dots\)</td><td>\(\dots\)</td> </tr> <tr> <td>\(60\)</td><td>\(\dots\)</td><td>\(\dots\)</td><td>\(\dots\)</td> </tr> <tr> <td>\(120\)</td><td>\(\dots\)</td><td>\(\dots\)</td><td>\(\dots\)</td> </tr> </table>

Hints

- Doubling means multiplying by \(2\). - Double the previous result to move one column to the right. - Look for the repeated-doubling pattern across each row. - Check the last column by multiplying the starting number by \(8\).

Solution

1. Starting with \(40\), double successively: \(40 \times 2 = 80\), \(80 \times 2 = 160\), and \(160 \times 2 = 320\). 2. Starting with \(60\), double successively: \(60 \times 2 = 120\), \(120 \times 2 = 240\), and \(240 \times 2 = 480\). 3. Starting with \(120\), double successively: \(120 \times 2 = 240\), \(240 \times 2 = 480\), and \(480 \times 2 = 960\).

Answer

For \(40\): \(80\), \(160\), \(320\) For \(60\): \(120\), \(240\), \(480\) For \(120\): \(240\), \(480\), \(960\)
5212014
A coin bank contains \(18\) nickels. Each nickel is worth \(5\) cents. How many cents are in the coin bank?

Hints

- Multiply the number of nickels by \(5\) cents. - Break \(18\) into tens and ones. - Add the partial products.

Solution

1. Multiply the number of nickels by the value of each nickel: \(18 \times 5\). 2. Decompose \(18\): \(18 = 10 + 8\). 3. Find the partial products: \(10 \times 5 = 50\) and \(8 \times 5 = 40\). 4. Add: \(50 + 40 = 90\).

Answer

The coin bank contains \(90\) cents.
5212024
A bakery has \(14\) full bags with \(6\) rolls in each bag. A hiking group wants to buy \(80\) rolls. Are there enough rolls? Justify your answer.

Hints

- Find the total number of rolls in the bags. - Decompose a factor by place value if helpful. - Compare the product with \(80\).

Solution

1. Find the total number of rolls: \(14 \times 6 = 84\). 2. Since \(84 > 80\), there are enough rolls.

Answer

Yes. The bakery has \(84\) rolls, which is enough for the order of \(80\).
5214594
Find each product using partial products. a) \(47 \times 3\) b) \(52 \times 6\) c) \(74 \times 4\) d) \(83 \times 5\) e) \(91 \times 8\)

Hints

- Break the two-digit factor into tens and ones. - Multiply each part by the one-digit factor. - Add the partial products. - Use basic multiplication facts to check your work.

Solution

1. For part a, \(40 \times 3 = 120\) and \(7 \times 3 = 21\). Then \(120 + 21 = 141\). 2. For part b, \(50 \times 6 = 300\) and \(2 \times 6 = 12\). Then \(300 + 12 = 312\). 3. For part c, \(70 \times 4 = 280\) and \(4 \times 4 = 16\). Then \(280 + 16 = 296\). 4. For part d, \(80 \times 5 = 400\) and \(3 \times 5 = 15\). Then \(400 + 15 = 415\). 5. For part e, \(90 \times 8 = 720\) and \(1 \times 8 = 8\). Then \(720 + 8 = 728\).

Answer

a) \(141\) b) \(312\) c) \(296\) d) \(415\) e) \(728\)
5279654
Complete the calculation for \(423 \times 6\). First decompose \(423\) by place value, then use partial products. \(423 \times 6 = (\underline{\quad} + \underline{\quad} + \underline{\quad}) \times 6\) \(= \dots \times 6 + \dots \times 6 + \dots \times 6\) \(= \dots + \dots + \dots\) \(= \dots\)

Hints

- Identify the hundreds, tens, and ones in \(423\). - Multiply each place-value part by \(6\). - Add the partial products carefully by place value.

Solution

1. Decompose \(423\) as \(400 + 20 + 3\). 2. Multiply each part by \(6\): \(400 \times 6 + 20 \times 6 + 3 \times 6\). 3. Add the partial products: \(2400 + 120 + 18 = 2538\).

Answer

\(423 \times 6 = (400 + 20 + 3) \times 6 = 400 \times 6 + 20 \times 6 + 3 \times 6 = 2400 + 120 + 18 = 2538\)
5279664
Lukas calculates \(197 \times 3\) as \(200 \times 3 - 3 \times 3\). a) Name the property he uses. b) Use his method to find \(197 \times 3\). c) Use a similar place-value decomposition to find \(305 \times 6\).

Hints

- Relate \(197\) to \(200\). - Multiply both parts by the one-digit factor. - Decompose \(305\) into hundreds and ones.

Solution

1. Lukas uses the distributive property with subtraction. 2. \(197 \times 3 = 200 \times 3 - 3 \times 3 = 600 - 9 = 591\). 3. Decompose \(305\) as \(300 + 5\): \(305 \times 6 = 300 \times 6 + 5 \times 6 = 1800 + 30 = 1830\).

Answer

a) Distributive property b) \(197 \times 3 = 200 \times 3 - 3 \times 3 = 591\) c) \(305 \times 6 = 300 \times 6 + 5 \times 6 = 1830\)
5363344
Complete the product wall. Multiply the two lower values to get the value above.
Figure for problem 536334

Hints

- Use division to find each missing bottom factor. - Multiply the two values in the second row for the top.

Solution

1. For the bottom-left value, solve \(x \times 3 = 6\), so \(x = 2\). 2. For the bottom-right value, solve \(3 \times y = 12\), so \(y = 4\). 3. The top is \(6 \times 12 = 72\).

Answer

Bottom row: \(2\), \(3\), \(4\) Second row: \(6\), \(12\) Top: \(72\)
5372944
The \(6 \times 12\) rectangular grid is split after \(10\) columns. a) What two partial products are shown by the two sections? b) Use the decomposition to find the total number of unit squares. c) Write an equation that shows the distributive property for this grid.
Figure for problem 537294

Hints

- Read each section as rows times columns. - The \(12\) columns are split into \(10\) columns and \(2\) columns. - Add the two partial products.

Solution

1. Part a: The left section has \(6\) rows and \(10\) columns, so it represents \(6 \times 10 = 60\). The right section has \(6\) rows and \(2\) columns, so it represents \(6 \times 2 = 12\). 2. Part b: Add the partial products: \(60 + 12 = 72\). 3. Part c: The grid shows \(6 \times (10 + 2) = 6 \times 10 + 6 \times 2\).

Answer

a) \(6 \times 10\) and \(6 \times 2\) b) \(60 + 12 = 72\) c) \(6 \times (10 + 2) = 6 \times 10 + 6 \times 2\)
5373784
A square mosaic is made from \(64\) tiles. Each tile costs \(3\) cents. How much does the entire mosaic cost? Use a helpful decomposition.
Figure for problem 537378

Hints

- Use the array to confirm the number of tiles. - Decompose \(64\) by place value before multiplying by \(3\).

Solution

1. The \(8 \times 8\) array contains \(64\) tiles. 2. Multiply the number of tiles by the cost per tile: \(64 \times 3\). 3. Decompose \(64\): \(60 \times 3 + 4 \times 3 = 180 + 12 = 192\) cents. 4. Convert to dollars: \(192\text{ cents} = \$1.92\).

Answer

The mosaic costs \(192\) cents, or \(\$1.92\).
5160544
You know these products: \(10 \times 9 = 90\) \(5 \times 9 = 45\) \(2 \times 9 = 18\) Use only these three products and addition or subtraction to find each product below. Show your reasoning. a) \(17 \times 9\) b) \(7 \times 9\) c) \(13 \times 9\)

Hints

- How can you combine \(10\), \(5\), and \(2\) to make \(17\), \(7\), or \(13\)? - You may add or subtract the known products. - For \(13\), can you first make a larger number and then subtract a part?

Solution

1. For a), write \(17\) as \(10 + 5 + 2\). Then \((10 + 5 + 2) \times 9 = 90 + 45 + 18 = 153\). 2. For b), write \(7\) as \(5 + 2\). Then \((5 + 2) \times 9 = 45 + 18 = 63\). 3. For c), write \(13\) as \(10 + 5 - 2\). Then \((10 + 5 - 2) \times 9 = 90 + 45 - 18 = 117\).

Answer

a) \(17 \times 9 = 90 + 45 + 18 = 153\) b) \(7 \times 9 = 45 + 18 = 63\) c) \(13 \times 9 = 90 + 45 - 18 = 117\)
5161644
For each product, choose mental math or a place-value strategy. Then find the product. a) \(8 \times 400\) b) \(3 \times 209\) c) \(70 \times 60\) d) \(248 \times 7\)

Hints

- Products involving multiples of \(10\) or \(100\) may be efficient to find mentally. - For other products, break the multi-digit factor into hundreds, tens, and ones. - Add the partial products carefully.

Solution

1. For a), use mental math: \(8 \times 4 = 32\), so \(8 \times 400 = 3200\). 2. For b), use a place-value strategy: \(3 \times 200 = 600\) and \(3 \times 9 = 27\). Then \(600 + 27 = 627\). 3. For c), use mental math: \(7 \times 6 = 42\), and the factors contain two factors of \(10\), so \(70 \times 60 = 4200\). 4. For d), use a place-value strategy: \(200 \times 7 = 1400\), \(40 \times 7 = 280\), and \(8 \times 7 = 56\). Then \(1400 + 280 + 56 = 1736\).

Answer

a) \(3200\) (mental math) b) \(627\) (place-value strategy) c) \(4200\) (mental math) d) \(1736\) (place-value strategy)
5161994
Six fourth-grade classes each collect \(48\) aluminum cans for a recycling project. How many cans do they collect altogether? First estimate the answer, and then find the exact product.

Hints

- Break \(48\) into tens and ones for the exact product. - Round \(48\) to a nearby multiple of \(10\) for the estimate. - Make sure your exact answer is close to your estimate.

Solution

1. Estimate by rounding \(48\) to \(50\): \(6 \times 50 = 300\). 2. Find the exact product using place value: \(6 \times 40 = 240\) and \(6 \times 8 = 48\). 3. Add the partial products: \(240 + 48 = 288\).

Answer

Estimate: about \(300\) cans Exact answer: \(288\) cans
5162004
A toy company packs \(135\) marbles in each bag. One box contains \(7\) bags. How many marbles are in the box? Use a place-value multiplication strategy.

Hints

- Break \(135\) into hundreds, tens, and ones. - Multiply each part by \(7\). - Check that your answer is greater than \(7 \times 100\).

Solution

1. Break \(135\) into \(100 + 30 + 5\). 2. Find the partial products: \(7 \times 100 = 700\), \(7 \times 30 = 210\), and \(7 \times 5 = 35\). 3. Add the partial products: \(700 + 210 + 35 = 945\).

Answer

There are \(945\) marbles in the box.
5162204
Estimate each product first. Then find the exact product and show your strategy. a) \(18 \times 7\) b) \(26 \times 4\) c) \(49 \times 3\)

Hints

- Break the two-digit factor into tens and ones for the exact product. - Choose a nearby or compatible number for the estimate. - Check that each exact product is reasonably close to its estimate.

Solution

1. For a), estimate with \(20 \times 7 = 140\). For the exact product, \(10 \times 7 = 70\) and \(8 \times 7 = 56\), so \(70 + 56 = 126\). 2. For b), use the compatible number \(25\) to estimate: \(25 \times 4 = 100\). For the exact product, \(20 \times 4 = 80\) and \(6 \times 4 = 24\), so \(80 + 24 = 104\). 3. For c), estimate with \(50 \times 3 = 150\). Since \(49\) is \(1\) less than \(50\), the exact product is \(150 - 3 = 147\).

Answer

a) Estimate: \(140\); exact product: \(126\) b) Estimate: \(100\); exact product: \(104\) c) Estimate: \(150\); exact product: \(147\)
5162214
A movie theater has \(9\) rows with \(23\) seats in each row. How many seats are there altogether? Estimate first, and then find the exact number.

Hints

- About how many seats would there be with \(10\) rows of \(20\) seats? - Break \(23\) into tens and ones. - Check that the exact answer is close to the estimate.

Solution

1. Estimate by using \(10 \times 20 = 200\). 2. For the exact product, break \(23\) into \(20 + 3\): \(9 \times 20 = 180\) and \(9 \times 3 = 27\). 3. Add the partial products: \(180 + 27 = 207\).

Answer

Estimate: about \(200\) seats Exact answer: \(207\) seats
5162224
Use an efficient strategy to find each product. Also give a reasonable estimate for each one. a) \(5 \times 198\) b) \(15 \times 6\) c) \(25 \times 8\)

Hints

- Is there a nearby number that makes a product easier to estimate? - Can you break a factor into tens and ones? - For \(198\), compare the product with the product using \(200\). - Check whether each exact product is reasonably close to its estimate.

Solution

1. For a), estimate with \(5 \times 200 = 1000\). For the exact product, subtract the extra \(5 \times 2\): \(1000 - 10 = 990\). 2. For b), estimate with \(20 \times 6 = 120\). For the exact product, \(10 \times 6 = 60\) and \(5 \times 6 = 30\), so \(60 + 30 = 90\). 3. For c), estimate with \(25 \times 10 = 250\). For the exact product, \(20 \times 8 = 160\) and \(5 \times 8 = 40\), so \(160 + 40 = 200\).

Answer

a) Estimate: about \(1000\); exact product: \(990\) b) Estimate: about \(120\); exact product: \(90\) c) Estimate: about \(250\); exact product: \(200\)
5163674
For each product, write three different multiplication equations. One factor in each equation must be a one-digit number from \(2\) through \(9\). a) \(120\) b) \(180\) c) \(360\)

Hints

- Divide each target by one-digit numbers from \(2\) through \(9\). - Keep a factor pair when the quotient is a whole number. - The other factor does not have to be a multiple of \(10\).

Solution

1. Test one-digit factors by dividing the target product and checking for whole-number quotients. 2. For \(120\), examples include \(2 \times 60\), \(3 \times 40\), and \(4 \times 30\). 3. For \(180\), examples include \(2 \times 90\), \(3 \times 60\), and \(4 \times 45\). 4. For \(360\), examples include \(3 \times 120\), \(4 \times 90\), and \(8 \times 45\).

Answer

a) One possible set is \(2 \times 60\), \(3 \times 40\), \(4 \times 30\). b) One possible set is \(2 \times 90\), \(3 \times 60\), \(4 \times 45\). c) One possible set is \(3 \times 120\), \(4 \times 90\), \(8 \times 45\). Other valid factor pairs are also correct.
5166924
Use these partial products: \(8 \times 500 = 4000\) \(8 \times 20 = 160\) \(8 \times 9 = 72\) Find each product. a) \(8 \times 520\) b) \(8 \times 29\) c) \(8 \times 529\) d) \(8 \times 509\)

Hints

- Identify the hundreds, tens, and ones in each factor. - Reuse the given partial products instead of multiplying from the beginning. - Which given parts combine to make \(529\)?

Solution

1. For a), combine the hundreds and tens partial products: \(4000 + 160 = 4160\). 2. For b), combine the tens and ones partial products: \(160 + 72 = 232\). 3. For c), add all three partial products: \(4000 + 160 + 72 = 4232\). 4. For d), combine the hundreds and ones partial products: \(4000 + 72 = 4072\).

Answer

a) \(4160\) b) \(232\) c) \(4232\) d) \(4072\)
5166934
A student used partial products to calculate \(4 \times 635\), but one partial product is wrong. \(4 \times 600=2400\) \(4 \times 30=120\) \(4 \times 5=25\) Find and correct the error. Then find the correct product. What would the product be for \(4 \times 630\)?

Hints

- Check each basic multiplication fact. - Correct the partial product before adding. - Compare \(635\) with \(630\) to identify which partial product is removed.

Solution

1. The first two partial products are correct. The error is \(4 \times 5=25\); the correct value is \(4 \times 5=20\). 2. Therefore, \(4 \times 635=2400+120+20=2540\). 3. For \(4 \times 630\), the ones partial product is not included: \(2400+120=2520\).

Answer

The incorrect partial product is \(4 \times 5=25\); it should be \(20\). \(4 \times 635=2540\). \(4 \times 630=2520\).
5177664
Find the products, then insert \(<\), \(>\), or \(=\). a) \(3 \times 27 \quad \dots \quad 4 \times 19\) b) \(5 \times 16 \quad \dots \quad 2 \times 40\) c) \(7 \times 12 \quad \dots \quad 6 \times 15\) Find the missing factor. d) \(\dots \times 14 = 70\)

Hints

- Calculate both products before comparing them. - Decompose two-digit factors into tens and ones when helpful. - For part d, determine how many groups of \(14\) make \(70\).

Solution

1. For part a, \(3 \times 27 = 81\) and \(4 \times 19 = 76\). Since \(81 > 76\), insert \(>\). 2. For part b, \(5 \times 16 = 80\) and \(2 \times 40 = 80\). Since \(80 = 80\), insert \(=\). 3. For part c, \(7 \times 12 = 84\) and \(6 \times 15 = 90\). Since \(84 < 90\), insert \(<\). 4. For part d, solve \(n \times 14 = 70\). Since \(70 \div 14 = 5\), the missing factor is \(5\).

Answer

a) \(>\) b) \(=\) c) \(<\) d) \(5\)
5183014
Fill in the missing numbers in each partial-products calculation. Problem 1: \(142 \times 4 = \dots\) \(100 \times 4 = \dots\) \(40 \times 4 = \dots\) \(2 \times 4 = \dots\) Problem 2: \(215 \times 3 = \dots\) \(200 \times 3 = \dots\) \(10 \times 3 = \dots\) \(5 \times 3 = \dots\)

Hints

- Use the given decomposition of each multi-digit factor. - Find each smaller product first. - Add the partial products to find the final product.

Solution

1. For Problem 1, the partial products are \(100 \times 4 = 400\), \(40 \times 4 = 160\), and \(2 \times 4 = 8\). Add them: \(400 + 160 + 8 = 568\). 2. For Problem 2, the partial products are \(200 \times 3 = 600\), \(10 \times 3 = 30\), and \(5 \times 3 = 15\). Add them: \(600 + 30 + 15 = 645\).

Answer

Problem 1: \(142 \times 4 = 568\); partial products: \(400\), \(160\), and \(8\) Problem 2: \(215 \times 3 = 645\); partial products: \(600\), \(30\), and \(15\)
5183234
An art-supply store receives \(5\) boxes of drawing pads. Each box contains \(138\) drawing pads. How many drawing pads are in the shipment? Use partial products.

Hints

- Decompose \(138\) into hundreds, tens, and ones. - Multiply \(5\) by each part. - Add the three partial products.

Solution

1. Decompose \(138\) as \(100 + 30 + 8\). 2. Multiply each part by \(5\): \(5 \times 100 = 500\), \(5 \times 30 = 150\), and \(5 \times 8 = 40\). 3. Add the partial products: \(500 + 150 + 40 = 690\).

Answer

There are \(690\) drawing pads in the shipment.
5183244
Two groups collect acorns for a wildlife center. The Blue Group fills \(3\) buckets with \(265\) acorns in each bucket. The Yellow Group fills \(4\) bags with \(198\) acorns in each bag. Which group collected more acorns? Support your answer with calculations using partial products.

Hints

- Find each group’s total separately. - Use partial products for each multiplication. - Compare the two totals.

Solution

1. For the Blue Group, decompose \(265\) as \(200 + 60 + 5\). Then \(3 \times 200 = 600\), \(3 \times 60 = 180\), and \(3 \times 5 = 15\). Add: \(600 + 180 + 15 = 795\). 2. For the Yellow Group, decompose \(198\) as \(100 + 90 + 8\). Then \(4 \times 100 = 400\), \(4 \times 90 = 360\), and \(4 \times 8 = 32\). Add: \(400 + 360 + 32 = 792\). 3. Compare the totals: \(795 > 792\).

Answer

The Blue Group collected more acorns: \(795\) acorns compared with \(792\) acorns.
5183444
A small movie-theater auditorium has \(138\) seats. The large auditorium has exactly three times as many seats. a) How many seats are in the large auditorium? b) Does the large auditorium have enough seats for a school group of \(400\) students? Explain.

Hints

- First find three times \(138\). - Decompose \(138\) into hundreds, tens, and ones. - Compare the product with \(400\).

Solution

1. Find the number of seats in the large auditorium by multiplying \(138\) by \(3\). 2. Use partial products: \(100 \times 3 = 300\), \(30 \times 3 = 90\), and \(8 \times 3 = 24\). 3. Add: \(300 + 90 + 24 = 414\). 4. Compare \(414\) with \(400\). Since \(414 > 400\), the large auditorium has enough seats.

Answer

a) The large auditorium has \(414\) seats. b) Yes. It has enough seats because \(414 > 400\).
5184174
Use the distributive property to evaluate each expression mentally. a) \(15 \times 3 + 5 \times 3\) b) \(22 \times 4 - 2 \times 4\) c) \(6 \times 17 - 6 \times 7\) d) \(12 \times 5 + 8 \times 5\)

Hints

- Identify the common factor in each expression. - Combine the other numbers to make a multiple of \(10\). - Multiply after rewriting the expression.

Solution

1. Part a: \((15 + 5) \times 3 = 20 \times 3 = 60\). 2. Part b: \((22 - 2) \times 4 = 20 \times 4 = 80\). 3. Part c: \(6 \times (17 - 7) = 6 \times 10 = 60\). 4. Part d: \((12 + 8) \times 5 = 20 \times 5 = 100\).

Answer

a) \(60\) b) \(80\) c) \(60\) d) \(100\)
5184184
Calculate the three products. Which product is closest to \(3000\)? A: \(428 \times 7\) B: \(596 \times 5\) C: \(382 \times 8\)

Hints

- Calculate each product. - Find the positive difference between each product and \(3000\). - The smallest difference identifies the closest product.

Solution

1. Calculate the products: A is \(428 \times 7=2996\), B is \(596 \times 5=2980\), and C is \(382 \times 8=3056\). 2. Find each distance from \(3000\): \(3000-2996=4\), \(3000-2980=20\), and \(3056-3000=56\). 3. Since \(4<20<56\), product A is closest to \(3000\).

Answer

A: \(428 \times 7=2996\) is closest to \(3000\).
5184194
Fill each blank with a digit that makes the equation true. a) \(\square 48\times 3=744\) b) \(125\times\square=750\) c) \(2\square 4\times 4=856\)

Hints

- Use inverse multiplication or division by a one-digit factor to recover a missing value. - Estimate the missing value before calculating. - Substitute your digit and verify the multiplication.

Solution

1. In part a, \(744\div 3=248\), so the missing digit is \(2\). 2. In part b, test the one-digit factor using multiplication: \(125\times 6=750\), so the missing factor is \(6\). 3. In part c, \(856\div 4=214\), so the missing digit is \(1\).

Answer

a) \(2\) b) \(6\) c) \(1\)
5184214
Compare these two values: a) Four times \(185\) b) Eight times \(92\) Which value is greater? Also find the difference between the two values.

Hints

- Calculate both products before comparing them. - To find the difference, subtract the smaller value from the greater value.

Solution

1. Calculate the first value: \(185 \times 4=740\). 2. Calculate the second value: \(92 \times 8=736\). 3. Compare: \(740>736\). 4. Find the difference: \(740-736=4\).

Answer

Four times \(185\) is greater. The difference is \(4\).
5184384
A bookstore receives \(6\) boxes of adventure books. Each box contains \(115\) books. Each book sells for \(\$9\). How much money will the bookstore earn if every book is sold?

Hints

- First find the total number of books. - Then multiply the number of books by the price of one book. - Check each multiplication using place value.

Solution

1. The shipment contains \(6 \times 115 = 690\) books. 2. The total sales amount is \(690 \times \$9 = \$6210\).

Answer

The bookstore will earn \(\$6210\).
5185144
Compare the expressions and insert \(<\), \(>\), or \(=\). \(7 \times 84\) ___ \(6 \times 98\)

Hints

- Calculate the left product first. - Then calculate the right product. - Compare the results. - Decompose each two-digit factor into tens and ones.

Solution

1. Decompose \(84\): \(7 \times 80 = 560\) and \(7 \times 4 = 28\). Thus, \(7 \times 84 = 588\). 2. Decompose \(98\): \(6 \times 90 = 540\) and \(6 \times 8 = 48\). Thus, \(6 \times 98 = 588\). 3. Since \(588 = 588\), insert \(=\).

Answer

\(=\)
5187114
Lina says, “These four expressions all have the same value.” A: \(3 \times 24\) B: \(4 \times 18\) C: \(6 \times 12\) D: \(8 \times 9\) Is Lina correct? Calculate each product and explain your answer.

Hints

- Break each two-digit factor into tens and ones. - Calculate each product separately. - Compare all four results.

Solution

1. Expression A: \(3 \times 24 = 3 \times 20 + 3 \times 4 = 60 + 12 = 72\). 2. Expression B: \(4 \times 18 = 4 \times 10 + 4 \times 8 = 40 + 32 = 72\). 3. Expression C: \(6 \times 12 = 6 \times 10 + 6 \times 2 = 60 + 12 = 72\). 4. Expression D: \(8 \times 9 = 72\). 5. All four expressions equal \(72\), so Lina is correct.

Answer

Yes. Lina is correct because \(3 \times 24 = 4 \times 18 = 6 \times 12 = 8 \times 9 = 72\).
5187334
Find each product. Which three problems have the same product? A) \(4 \times 16\) B) \(2 \times 32\) C) \(5 \times 13\) D) \(8 \times 8\) E) \(3 \times 21\)

Hints

- Decompose two-digit factors into tens and ones. - Find each product. - Compare all five results.

Solution

1. A: \(4 \times 10 = 40\) and \(4 \times 6 = 24\), so \(4 \times 16 = 64\). 2. B: \(2 \times 30 = 60\) and \(2 \times 2 = 4\), so \(2 \times 32 = 64\). 3. C: \(5 \times 10 = 50\) and \(5 \times 3 = 15\), so \(5 \times 13 = 65\). 4. D: \(8 \times 8 = 64\). 5. E: \(3 \times 20 = 60\) and \(3 \times 1 = 3\), so \(3 \times 21 = 63\). 6. Problems A, B, and D all have a product of \(64\).

Answer

Problems A, B, and D have the same product, \(64\).
5187344
Compare the products. Insert \(<\), \(>\), or \(=\). a) \(4 \times 17 \quad \square \quad 3 \times 23\) b) \(6 \times 14 \quad \square \quad 7 \times 12\) c) \(5 \times 18 \quad \square \quad 4 \times 22\) d) \(2 \times 49 \quad \square \quad 3 \times 33\)

Hints

- Calculate the product on each side before comparing. - Write down the partial products. - Decompose a number such as \(17\) as \(10 + 7\).

Solution

1. For part a, \(4 \times 17 = 40 + 28 = 68\), and \(3 \times 23 = 60 + 9 = 69\). Since \(68 < 69\), insert \(<\). 2. For part b, \(6 \times 14 = 60 + 24 = 84\), and \(7 \times 12 = 70 + 14 = 84\). Since \(84 = 84\), insert \(=\). 3. For part c, \(5 \times 18 = 50 + 40 = 90\), and \(4 \times 22 = 80 + 8 = 88\). Since \(90 > 88\), insert \(>\). 4. For part d, \(2 \times 49 = 80 + 18 = 98\), and \(3 \times 33 = 90 + 9 = 99\). Since \(98 < 99\), insert \(<\).

Answer

a) \(<\) b) \(=\) c) \(>\) d) \(<\)
5187404
A class has \(24\) students. For an art project, each student receives \(5\) red sheets of paper and \(3\) green sheets. How many sheets are distributed altogether? Solve the problem in two different ways.

Hints

- Find how many sheets one student receives. - You can also find the red and green totals separately. - Both methods should give the same total.

Solution

1. Combine the sheets for one student, then multiply: \(5 + 3 = 8\), and \(24 \times 8 = 192\). 2. Find each color separately, then add: \(24 \times 5 = 120\), \(24 \times 3 = 72\), and \(120 + 72 = 192\).

Answer

One method is \(24 \times (5 + 3) = 24 \times 8 = 192\). Another method is \(24 \times 5 + 24 \times 3 = 120 + 72 = 192\). The class receives \(192\) sheets altogether.
5188014
Find each product. Which product is greatest? a) \(214 \times 4\) b) \(321 \times 3\) c) \(450 \times 2\)

Hints

- Decompose each multi-digit factor into hundreds, tens, and ones. - Add the partial products. - Compare the three final products.

Solution

1. For part a, \(200 \times 4 = 800\), \(10 \times 4 = 40\), and \(4 \times 4 = 16\). Add: \(800 + 40 + 16 = 856\). 2. For part b, \(300 \times 3 = 900\), \(20 \times 3 = 60\), and \(1 \times 3 = 3\). Add: \(900 + 60 + 3 = 963\). 3. For part c, \(400 \times 2 = 800\) and \(50 \times 2 = 100\). Add: \(800 + 100 = 900\). 4. Compare: \(963 > 900 > 856\). The greatest product is \(963\).

Answer

a) \(856\) b) \(963\) c) \(900\) Part b has the greatest product: \(321 \times 3 = 963\).
5188024
Fill in the missing numbers in the partial-products work: \(123 \times 4 = \square\) \(\rule{2cm}{0.4pt}\) \(\square \times 4 = 400\) \(20 \times 4 = \square\) \(\square \times 4 = 12\)

Hints

- Break \(123\) into hundreds, tens, and ones. - Use the given partial products to find the missing factors. - Add the three partial products.

Solution

1. The hundreds part must be \(100\), because \(100 \times 4 = 400\). 2. Multiply the tens: \(20 \times 4 = 80\). 3. The ones part must be \(3\), because \(3 \times 4 = 12\). 4. Add the partial products: \(400 + 80 + 12 = 492\).

Answer

\(123 \times 4 = 492\) \(100 \times 4 = 400\) \(20 \times 4 = 80\) \(3 \times 4 = 12\)
5188064
Compare the products. Write \(<\), \(>\), or \(=\) in each blank. a) \(12 \times 8\) ______ \(16 \times 6\) b) \(24 \times 3\) ______ \(18 \times 4\) c) \(15 \times 7\) ______ \(13 \times 8\)

Hints

- Find each product before comparing. - You can break each two-digit factor into tens and ones. - Compare the two results in each part.

Solution

1. For part a, \(12 \times 8 = 96\) and \(16 \times 6 = 96\), so the products are equal. 2. For part b, \(24 \times 3 = 72\) and \(18 \times 4 = 72\), so the products are equal. 3. For part c, \(15 \times 7 = 105\) and \(13 \times 8 = 104\), so \(105 > 104\).

Answer

a) \(=\) b) \(=\) c) \(>\)
5188074
Fill in the missing numbers in each partial-products method. a) \(47 \times 6 =\) ______ \(40 \times 6 =\) ______ \(7 \times 6 =\) ______ \(\text{______} + \text{______} = \text{______}\) b) What multiplication equation is represented by this work? \(\text{______} \times 8 = \text{______}\) \(30 \times 8 = 240\) \(6 \times 8 = 48\) \(240 + 48 = 288\)

Hints

- Notice how each two-digit number is broken into tens and ones. - Find the partial products, then add them. - In part b, combine the two partial factors to find the original factor.

Solution

1. For part a, multiply the tens: \(40 \times 6 = 240\). 2. Multiply the ones: \(7 \times 6 = 42\). 3. Add the partial products: \(240 + 42 = 282\), so \(47 \times 6 = 282\). 4. For part b, the partial factors are \(30\) and \(6\), so the first factor is \(30 + 6 = 36\). 5. The equation is \(36 \times 8 = 288\).

Answer

a) \(47 \times 6 = 282\) \(40 \times 6 = 240\) \(7 \times 6 = 42\) \(240 + 42 = 282\) b) \(36 \times 8 = 288\)
5188584
Calculate and compare the products. Replace each box with \(<\), \(>\), or \(=\). a) \(178 \times 4\;\square\;142 \times 5\) b) \(235 \times 3\;\square\;118 \times 6\) c) \(156 \times 7\;\square\;182 \times 6\)

Hints

- Calculate both products in each comparison. - Compare the products from the greatest place value to the least. - Estimate first to check whether each exact result is reasonable.

Solution

1. For a), \(178 \times 4=712\) and \(142 \times 5=710\), so \(712>710\). 2. For b), \(235 \times 3=705\) and \(118 \times 6=708\), so \(705<708\). 3. For c), \(156 \times 7=1092\) and \(182 \times 6=1092\), so the products are equal.

Answer

a) \(>\) b) \(<\) c) \(=\)
5189994
Lena wrote two different methods. Method A: \(215 + 215 + 215 + 215\) Method B: \(251 + 251 + 251 + 251\) Which method represents \(4 \times 215\)? Find the product.

Hints

- Think about what \(4 \times 215\) means as repeated addition. - Compare the digits in \(215\) and \(251\) carefully. - Break \(215\) into hundreds, tens, and ones.

Solution

1. The expression \(4 \times 215\) means four groups of \(215\), so Method A represents the multiplication. 2. Use partial products: \(4 \times 200 = 800\), \(4 \times 10 = 40\), and \(4 \times 5 = 20\). 3. Add: \(800 + 40 + 20 = 860\).

Answer

Method A represents the multiplication. The product is \(860\).
5190004
A garden center packs \(124\) tulip bulbs in each box. A worker prepares \(7\) boxes. How many tulip bulbs are there in all? a) First write the situation as repeated addition. b) Then find the total with multiplication. Break \(124\) into hundreds, tens, and ones.

Hints

- Write \(124\) once for each of the \(7\) boxes. - Find \(7 \times 100\), \(7 \times 20\), and \(7 \times 4\). - Add the partial products.

Solution

1. Seven boxes of \(124\) bulbs can be written as \(124 + 124 + 124 + 124 + 124 + 124 + 124\). 2. Find the partial products: \(7 \times 100 = 700\), \(7 \times 20 = 140\), and \(7 \times 4 = 28\). 3. Add the partial products: \(700 + 140 + 28 = 868\).

Answer

a) \(124 + 124 + 124 + 124 + 124 + 124 + 124\) b) There are \(868\) tulip bulbs in all.
5190084
A warehouse has \(4\) shelves. Each shelf holds \(218\) bags of flour. How many bags of flour are on the shelves in all? Break \(218\) into hundreds, tens, and ones and use partial products.

Hints

- Break the three-digit number into hundreds, tens, and ones. - Multiply each part by \(4\). - Add the three partial products.

Solution

1. Break apart \(218\) as \(200 + 10 + 8\). 2. Find the partial products: \(200 \times 4 = 800\), \(10 \times 4 = 40\), and \(8 \times 4 = 32\). 3. Add: \(800 + 40 + 32 = 872\).

Answer

There are \(872\) bags of flour on the shelves in all.
5190094
A school bus travels \(124\) miles each school day. How many miles does it travel during one school week, Monday through Friday? Use partial products.

Hints

- Count the school days from Monday through Friday. - Decide how many times the daily distance must be counted. - Break \(124\) into hundreds, tens, and ones, then multiply and add. - Write the final answer in miles.

Solution

1. There are \(5\) school days from Monday through Friday. 2. Break apart \(124\) as \(100 + 20 + 4\). 3. Find the partial products: \(100 \times 5 = 500\), \(20 \times 5 = 100\), and \(4 \times 5 = 20\). 4. Add: \(500 + 100 + 20 = 620\).

Answer

The bus travels \(620\) miles during the school week.
5191294
Group equal addends. Rewrite the expression as a sum of products, then evaluate it. \(9 + 13 + 9 + 11 + 13 + 9 + 11 + 13 + 9\)

Hints

- Organize or mark matching addends before counting them. - Write one product for each different addend. - Check that every original addend is represented exactly once.

Solution

1. The addend \(9\) appears \(4\) times, \(13\) appears \(3\) times, and \(11\) appears \(2\) times. 2. Rewrite the expression as \(4 \times 9 + 3 \times 13 + 2 \times 11\). 3. Evaluate: \(4 \times 9 = 36\), \(3 \times 13 = 39\), and \(2 \times 11 = 22\). 4. Add the products: \(36 + 39 + 22 = 97\).

Answer

\(4 \times 9 + 3 \times 13 + 2 \times 11 = 97\)
5193514
Emma solved two multiplication problems. Check her work using related division equations. a) First calculate \(236\times 4\). What division equation can check the product? b) Emma also wrote \(158\times 7=1116\). Use division to show that her product is incorrect. Then find the correct product.

Hints

- Dividing a product by one factor should give the other factor. - A related division equation reverses the multiplication. - A remainder or a different quotient shows that the stated product is incorrect.

Solution

1. Part a: \(236\times 4=944\). The related check is \(944\div 4=236\). 2. Part b: \(1116\div 7=159\text{ R }3\), not \(158\), so Emma’s product is incorrect. 3. The correct product is \(158\times 7=1106\). 4. Check: \(1106\div 7=158\).

Answer

a) \(236\times 4=944\); check: \(944\div 4=236\) b) \(1116\div 7=159\text{ R }3\), so the stated product is incorrect. The correct product is \(1106\).
5194714
Write \(<\), \(>\), or \(=\) in each box. a) \(160 \times 4 \quad \square \quad 210 \times 3\) b) \(150 \times 6 \quad \square \quad 300 \times 3\) c) \(120 \times 8 \quad \square \quad 240 \times 4\)

Hints

- Find the product on each side. - Use place value and a related basic fact when a factor is a multiple of \(10\). - Compare the two products.

Solution

1. For part a, \(160 \times 4 = 640\) and \(210 \times 3 = 630\), so \(640 > 630\). 2. For part b, \(150 \times 6 = 900\) and \(300 \times 3 = 900\), so the products are equal. 3. For part c, \(120 \times 8 = 960\) and \(240 \times 4 = 960\), so the products are equal.

Answer

a) \(>\) b) \(=\) c) \(=\)
5194974
A school library has \(3\) new bookcases. Each bookcase holds \(245\) books. How many books can the new bookcases hold in all? Show your work by breaking apart \(245\).

Hints

- Break \(245\) into hundreds, tens, and ones. - Multiply each part by \(3\). - Add the partial products.

Solution

1. Break apart \(245\) as \(200 + 40 + 5\). 2. Find the partial products: \(200 \times 3 = 600\), \(40 \times 3 = 120\), and \(5 \times 3 = 15\). 3. Add: \(600 + 120 + 15 = 735\).

Answer

The new bookcases can hold \(735\) books in all.
5195024
Lara has \(6\) bags with \(148\) beads in each bag. She starts using partial products: \(100 \times 6 = 600\) \(40 \times 6 = 240\) What partial product is missing? How many beads does Lara have in all?

Hints

- Identify which place-value part of \(148\) has not been used. - Multiply that part by \(6\). - Add all three partial products.

Solution

1. The ones part of \(148\) has not been multiplied, so the missing partial product is \(8 \times 6 = 48\). 2. Add all the partial products: \(600 + 240 + 48 = 888\).

Answer

The missing partial product is \(8 \times 6 = 48\). Lara has \(888\) beads in all.
5195054
A teacher buys \(4\) packages of notebooks. Each package contains \(136\) notebooks. How many notebooks does the teacher buy in all? Use partial products.

Hints

- Break \(136\) into hundreds, tens, and ones. - Multiply each part by \(4\). - Add the partial products.

Solution

1. Break apart \(136\) as \(100 + 30 + 6\). 2. Find the partial products: \(4 \times 100 = 400\), \(4 \times 30 = 120\), and \(4 \times 6 = 24\). 3. Add: \(400 + 120 + 24 = 544\).

Answer

The teacher buys \(544\) notebooks in all.
5195594
Find \(138 \times 4\). Then find \(92 \times 8\).

Hints

- Break each larger factor into place-value parts. - Use basic multiplication facts for each part. - Record each partial product. - Add the partial products for each multiplication problem.

Solution

1. For \(138 \times 4\), find the partial products: \(100 \times 4 = 400\), \(30 \times 4 = 120\), and \(8 \times 4 = 32\). 2. Add: \(400 + 120 + 32 = 552\). 3. For \(92 \times 8\), find the partial products: \(90 \times 8 = 720\) and \(2 \times 8 = 16\). 4. Add: \(720 + 16 = 736\).

Answer

\(138 \times 4 = 552\) \(92 \times 8 = 736\)
5196304
Use a nearby multiple of \(10\) and the distributive property to calculate mentally. a) \(59 \times 3\) b) \(38 \times 7\)

Hints

- Identify the next multiple of \(10\). - Multiply using the multiple of \(10\), then subtract the extra part. - Apply the one-digit factor to both terms.

Solution

1. For a), write \(59\) as \(60 - 1\): \((60 - 1) \times 3 = 60 \times 3 - 1 \times 3 = 180 - 3 = 177\). 2. For b), write \(38\) as \(40 - 2\): \((40 - 2) \times 7 = 40 \times 7 - 2 \times 7 = 280 - 14 = 266\).

Answer

a) \(177\) b) \(266\)
5196314
Use the distributive property to calculate mentally. Show how you decompose one factor. a) \(104 \times 8\) b) \(9 \times 198\)

Hints

- Decompose a factor using \(100\) or \(200\). - Decide whether a sum or a difference is more convenient. - Multiply each part, then combine the partial products.

Solution

1. For a), decompose \(104\) as \(100 + 4\): \(100 \times 8 + 4 \times 8 = 800 + 32 = 832\). 2. For b), decompose \(198\) as \(200 - 2\): \(9 \times 200 - 9 \times 2 = 1800 - 18 = 1782\).

Answer

a) \(104 = 100 + 4\), so \(100 \times 8 + 4 \times 8 = 832\). b) \(198 = 200 - 2\), so \(9 \times 200 - 9 \times 2 = 1782\).
5197474
A large box of pencils contains \(2\) packs of \(100\) pencils and \(4\) packs of \(10\) pencils. a) How many pencils are in one large box? b) How many pencils are in \(4\) large boxes?

Hints

- First find the number of pencils in the hundreds packs and the tens packs. - Add those amounts to find the number in one large box. - Multiply the result from part a by \(4\) for part b.

Solution

1. For part a, \(2 \times 100 = 200\) and \(4 \times 10 = 40\). Then \(200 + 40 = 240\). 2. For part b, multiply \(240\) by \(4\). The partial products are \(200 \times 4 = 800\) and \(40 \times 4 = 160\). 3. Add: \(800 + 160 = 960\).

Answer

a) One large box contains \(240\) pencils. b) Four large boxes contain \(960\) pencils.
5198314
Compare the products. Write \(<\), \(>\), or \(=\) in each box. a) \(120 \times 4 \quad \square \quad 240 \times 2\) b) \(303 \times 3 \quad \square \quad 450 \times 2\) c) \(112 \times 4 \quad \square \quad 221 \times 2\) d) \(205 \times 4 \quad \square \quad 410 \times 2\)

Hints

- Find the product on the left side of each comparison. - Find the product on the right side. - Look for relationships such as doubling one factor while halving the other. - Compare the final products.

Solution

1. For part a, \(120 \times 4 = 480\) and \(240 \times 2 = 480\), so the products are equal. 2. For part b, \(303 \times 3 = 909\) and \(450 \times 2 = 900\), so \(909 > 900\). 3. For part c, \(112 \times 4 = 448\) and \(221 \times 2 = 442\), so \(448 > 442\). 4. For part d, \(205 \times 4 = 820\) and \(410 \times 2 = 820\), so the products are equal.

Answer

a) \(120 \times 4 = 240 \times 2\) b) \(303 \times 3 > 450 \times 2\) c) \(112 \times 4 > 221 \times 2\) d) \(205 \times 4 = 410 \times 2\)
5198524
Compare the products. Write \(>\), \(<\), or \(=\) in each box. a) \(14 \times 8 \quad \square \quad 16 \times 7\) b) \(22 \times 6 \quad \square \quad 33 \times 4\) c) \(45 \times 4 \quad \square \quad 28 \times 6\) d) \(19 \times 9 \quad \square \quad 25 \times 7\)

Hints

- Find the product on each side. - Use partial products when needed. - Compare the two results in each part.

Solution

1. For part a, \(14 \times 8 = 112\) and \(16 \times 7 = 112\), so the products are equal. 2. For part b, \(22 \times 6 = 132\) and \(33 \times 4 = 132\), so the products are equal. 3. For part c, \(45 \times 4 = 180\) and \(28 \times 6 = 168\), so \(180 > 168\). 4. For part d, \(19 \times 9 = 171\) and \(25 \times 7 = 175\), so \(171 < 175\).

Answer

a) \(=\) b) \(=\) c) \(>\) d) \(<\)
5198594
Compare the products. Write \(<\), \(>\), or \(=\) in each box. a) \(124 \times 3 \quad \square \quad 185 \times 2\) b) \(215 \times 4 \quad \square \quad 430 \times 2\) c) \(132 \times 6 \quad \square \quad 265 \times 3\)

Hints

- Find the product on the left side. - Find the product on the right side. - Look for factor relationships that may help, especially in part b. - Compare the final products.

Solution

1. For part a, \(124 \times 3 = 372\) and \(185 \times 2 = 370\), so \(372 > 370\). 2. For part b, \(215 \times 4 = 860\) and \(430 \times 2 = 860\), so the products are equal. 3. For part c, \(132 \times 6 = 792\) and \(265 \times 3 = 795\), so \(792 < 795\).

Answer

a) \(>\) b) \(=\) c) \(<\)
5200094
A garden center delivers \(8\) boxes of seedlings. Each box contains \(112\) seedlings. How many seedlings are delivered in all? Break \(112\) into hundreds, tens, and ones and use partial products.

Hints

- Break \(112\) into hundreds, tens, and ones. - Multiply each part by \(8\). - Add the partial products.

Solution

1. Break apart \(112\) as \(100 + 10 + 2\). 2. Find the partial products: \(100 \times 8 = 800\), \(10 \times 8 = 80\), and \(2 \times 8 = 16\). 3. Add: \(800 + 80 + 16 = 896\).

Answer

The garden center delivers \(896\) seedlings in all.
5200134
Consider the expression \(214 + 214 + 214 + 214\). a) Find the sum by adding step by step. b) Write and solve the related multiplication equation. c) Compare the two results. What do you notice?

Hints

- Count how many times \(214\) appears in the sum. - Break \(214\) into hundreds, tens, and ones for the multiplication. - Compare the two final results.

Solution

1. Add step by step: \(214 + 214 = 428\), \(428 + 214 = 642\), and \(642 + 214 = 856\). 2. Since \(214\) is added four times, the related multiplication equation is \(4 \times 214\). 3. Use partial products: \(4 \times 200 = 800\), \(4 \times 10 = 40\), and \(4 \times 4 = 16\). Then \(800 + 40 + 16 = 856\). 4. Both methods give the same result.

Answer

a) \(856\) b) \(4 \times 214 = 856\) c) The results are equal.
5200144
Decide whether this statement is true or false: “The sum \(136 + 136 + 136 + 136 + 136\) has the same value as \(5 \times 136\).” Find both values and briefly explain your answer.

Hints

- Find the value of the repeated addition and the multiplication separately. - Compare the two values. - Think about what the factor \(5\) tells you about the number of equal addends.

Solution

1. Add the five equal addends: \(136 + 136 = 272\), \(272 + 136 = 408\), \(408 + 136 = 544\), and \(544 + 136 = 680\). 2. Use partial products for \(5 \times 136\): \(5 \times 100 = 500\), \(5 \times 30 = 150\), and \(5 \times 6 = 30\). Then \(500 + 150 + 30 = 680\). 3. The statement is true because multiplication represents repeated addition of equal groups.

Answer

The statement is true. Both expressions equal \(680\). The multiplication represents adding \(136\) five times.
5202074
Fill in each blank to complete the partial-products work. a) \(17 \times 4 = (10 \times 4) + (\square \times 4) = 40 + \square = \square\) b) \(25 \times 3 = (\square \times 3) + (5 \times 3) = \square + 15 = \square\) c) \(13 \times 6 = 10 \times \square + 3 \times \square = \square + \square = \square\)

Hints

- Notice how each two-digit factor is broken into tens and ones. - Use the same one-digit factor in both partial products. - Add the partial products to find the total.

Solution

1. For part a, break \(17\) into \(10 + 7\). Then \(10 \times 4 = 40\), \(7 \times 4 = 28\), and \(40 + 28 = 68\). 2. For part b, break \(25\) into \(20 + 5\). Then \(20 \times 3 = 60\), \(5 \times 3 = 15\), and \(60 + 15 = 75\). 3. For part c, break \(13\) into \(10 + 3\). Then \(10 \times 6 = 60\), \(3 \times 6 = 18\), and \(60 + 18 = 78\).

Answer

a) \(17 \times 4 = (10 \times 4) + (7 \times 4) = 40 + 28 = 68\) b) \(25 \times 3 = (20 \times 3) + (5 \times 3) = 60 + 15 = 75\) c) \(13 \times 6 = 10 \times 6 + 3 \times 6 = 60 + 18 = 78\)
5202334
Write \(<\), \(>\), or \(=\) in each box. a) \(128 \times 4 \quad \square \quad 256 \times 2\) b) \(115 \times 7 \quad \square \quad 132 \times 6\) c) \(219 \times 3 \quad \square \quad 164 \times 4\)

Hints

- Find the product on the left side of each comparison. - Find the product on the right side. - Compare the two results. - In part c, check the ones digits carefully.

Solution

1. For part a, \(128 \times 4 = 512\) and \(256 \times 2 = 512\), so the products are equal. 2. For part b, \(115 \times 7 = 805\) and \(132 \times 6 = 792\), so \(805 > 792\). 3. For part c, \(219 \times 3 = 657\) and \(164 \times 4 = 656\), so \(657 > 656\).

Answer

a) \(=\) b) \(>\) c) \(>\)
5202364
A garden center packs \(14\) flowers in each box. a) Find the number of flowers in \(2\) boxes, \(10\) boxes, and \(20\) boxes. b) How many flowers are in \(12\) boxes? Use your results from part a. c) How many flowers are in \(22\) boxes? Use your results from part a.

Hints

- Break \(12\) into \(10 + 2\). - Break \(22\) into \(20 + 2\). - Add the useful results from part a.

Solution

1. For part a, \(2 \times 14 = 28\), \(10 \times 14 = 140\), and \(20 \times 14 = 280\). 2. For part b, combine the amounts for \(10\) boxes and \(2\) boxes: \(140 + 28 = 168\). 3. For part c, combine the amounts for \(20\) boxes and \(2\) boxes: \(280 + 28 = 308\).

Answer

a) \(28\), \(140\), and \(280\) flowers b) \(168\) flowers c) \(308\) flowers
5202394
Find each product. a) \(145 \times 3\) b) \(232 \times 3\) c) \(118 \times 7\) d) \(106 \times 7\)

Hints

- Use the factor shown in each multiplication problem. - Break each three-digit number into place-value parts if helpful. - Add the partial products carefully.

Solution

1. For a), \(145 \times 3 = 435\). 2. For b), \(232 \times 3 = 696\). 3. For c), \(118 \times 7 = 826\). 4. For d), \(106 \times 7 = 742\).

Answer

a) \(435\) b) \(696\) c) \(826\) d) \(742\)
5202594
Compare the products. Write \(<\), \(>\), or \(=\) in each box. Use partial products to check. a) \(105 \times 4 \square 104 \times 5\) b) \(108 \times 3 \square 103 \times 8\) c) \(102 \times 9 \square 109 \times 2\)

Hints

- Estimate by comparing the hundreds before calculating. - Find both products in each part. - Break each three-digit factor into hundreds and ones if helpful.

Solution

1. For part a, \(105 \times 4 = 420\) and \(104 \times 5 = 520\), so \(420 < 520\). 2. For part b, \(108 \times 3 = 324\) and \(103 \times 8 = 824\), so \(324 < 824\). 3. For part c, \(102 \times 9 = 918\) and \(109 \times 2 = 218\), so \(918 > 218\).

Answer

a) \(105 \times 4 < 104 \times 5\) b) \(108 \times 3 < 103 \times 8\) c) \(102 \times 9 > 109 \times 2\)
5202694
Fill in the missing numbers in each partial-products method. a) \(57 \times 5 = \dots\) \(50 \times 5 = \dots\) \(7 \times 5 = \dots\) b) \(84 \times 4 = \dots\) \(\dots \times 4 = 320\) \(\dots \times 4 = 16\) c) \(29 \times 9 = \dots\) \(20 \times \dots = 180\) \(9 \times \dots = 81\)

Hints

- Identify how each two-digit factor is broken into tens and ones. - Use the given partial product to work backward when a factor is missing. - Add the partial products to find the total.

Solution

1. For part a, \(50 \times 5 = 250\) and \(7 \times 5 = 35\). Then \(250 + 35 = 285\). 2. For part b, the missing partial factors are \(80\) and \(4\), because \(80 \times 4 = 320\) and \(4 \times 4 = 16\). Then \(320 + 16 = 336\). 3. For part c, both missing factors are \(9\), because \(20 \times 9 = 180\) and \(9 \times 9 = 81\). Then \(180 + 81 = 261\).

Answer

a) \(57 \times 5 = 285\), \(50 \times 5 = 250\), and \(7 \times 5 = 35\) b) \(84 \times 4 = 336\), \(80 \times 4 = 320\), and \(4 \times 4 = 16\) c) \(29 \times 9 = 261\), \(20 \times 9 = 180\), and \(9 \times 9 = 81\)
5202734
Compare the products. Write \(<\), \(>\), or \(=\) in each box. a) \(18 \times 7 \square 15 \times 8\) b) \(24 \times 4 \square 12 \times 8\) c) \(13 \times 9 \square 16 \times 7\)

Hints

- Find the product on the left and the product on the right. - Compare the two values. - Choose the symbol that makes each statement true.

Solution

1. For part a, \(18 \times 7 = 126\) and \(15 \times 8 = 120\), so \(126 > 120\). 2. For part b, \(24 \times 4 = 96\) and \(12 \times 8 = 96\), so the products are equal. 3. For part c, \(13 \times 9 = 117\) and \(16 \times 7 = 112\), so \(117 > 112\).

Answer

a) \(18 \times 7 > 15 \times 8\) b) \(24 \times 4 = 12 \times 8\) c) \(13 \times 9 > 16 \times 7\)
5202744
Find and compare the products. Write \(<\), \(>\), or \(=\) in each box. a) \(46 \times 4 \square 62 \times 3\) b) \(38 \times 5 \square 94 \times 2\)

Hints

- Find each product separately. - Break the two-digit factors into tens and ones if helpful. - Compare the final products.

Solution

1. For part a, \(46 \times 4 = 184\) and \(62 \times 3 = 186\), so \(184 < 186\). 2. For part b, \(38 \times 5 = 190\) and \(94 \times 2 = 188\), so \(190 > 188\).

Answer

a) \(46 \times 4 < 62 \times 3\) b) \(38 \times 5 > 94 \times 2\)
5202754
Complete each partial-products method. a) \(54 \times 6\) \(50 \times 6 = \dots\) \(4 \times 6 = \dots\) \(54 \times 6 = \dots\) b) \(87 \times 3\) \(80 \times 3 = \dots\) \(7 \times 3 = \dots\) \(87 \times 3 = \dots\) c) \(69 \times 4\) \(60 \times 4 = \dots\) \(9 \times 4 = \dots\) \(69 \times 4 = \dots\)

Hints

- Identify the tens and ones parts of each two-digit factor. - Multiply both parts by the one-digit factor. - Add the partial products.

Solution

1. For part a, \(50 \times 6 = 300\) and \(4 \times 6 = 24\). Then \(300 + 24 = 324\). 2. For part b, \(80 \times 3 = 240\) and \(7 \times 3 = 21\). Then \(240 + 21 = 261\). 3. For part c, \(60 \times 4 = 240\) and \(9 \times 4 = 36\). Then \(240 + 36 = 276\).

Answer

a) \(50 \times 6 = 300\), \(4 \times 6 = 24\), and \(54 \times 6 = 324\) b) \(80 \times 3 = 240\), \(7 \times 3 = 21\), and \(87 \times 3 = 261\) c) \(60 \times 4 = 240\), \(9 \times 4 = 36\), and \(69 \times 4 = 276\)
5202814
Complete both parts. a) Multiply each number by \(6\): - \(110\) - \(145\) - \(160\) b) The same missing factor is used in all three products. First use \(120 \times \square = 600\) to find the factor. Then find: - \(140 \times \square\) - \(180 \times \square\)

Hints

- In part a), multiply each number by \(6\). - In part b), ask which factor makes \(120 \times \square = 600\). - Use a related basic fact, such as \(12 \times \square = 60\), if helpful. - Use the same factor for the other products in part b).

Solution

1. For a), \(110 \times 6 = 660\), \(145 \times 6 = 870\), and \(160 \times 6 = 960\). 2. For b), the missing factor is \(5\), because \(120 \times 5 = 600\). 3. Using the same factor, \(140 \times 5 = 700\) and \(180 \times 5 = 900\).

Answer

a) \(660\), \(870\), \(960\) b) Factor: \(5\); products: \(700\), \(900\)
5202834
A gardener plants \(4\) rows with \(14\) seedlings in each row. a) How many seedlings are planted in all? b) A large park will have \(40\) such rows. Find the number of seedlings in two ways: 1. Use your result from part a and multiply it by an appropriate number. 2. Break \(40 \times 14\) into two partial products.

Hints

- First find the number of seedlings in \(4\) rows. - Compare \(40\) rows with \(4\) rows. - Think about what happens to a product when one factor is multiplied by \(10\). - For the second method, break \(14\) into tens and ones.

Solution

1. For part a, \(4 \times 10 = 40\) and \(4 \times 4 = 16\). Then \(40 + 16 = 56\). 2. For the first method in part b, \(40\) rows is ten times as many as \(4\) rows, so \(56 \times 10 = 560\). 3. For the second method, break \(14\) into \(10 + 4\): \(40 \times 10 = 400\) and \(40 \times 4 = 160\). Then \(400 + 160 = 560\).

Answer

a) \(56\) seedlings b) \(560\) seedlings
5203894
Fill in the missing values to complete each distributive-property calculation. a) \(14 \times 6 = 10 \times 6 + \dots \times 6 = \dots + \dots = \dots\) b) \(18 \times 4 = 20 \times 4 - \dots \times 4 = \dots - \dots = \dots\) c) \(23 \times 3 = (20 + 3) \times 3 = \dots \times 3 + \dots \times 3 = \dots + \dots = \dots\)

Hints

- Decompose the two-digit factor into tens and ones. - Pay attention to whether the decomposition uses addition or subtraction. - Multiply each part, then combine the partial products.

Solution

1. For a), \(14 \times 6 = 10 \times 6 + 4 \times 6 = 60 + 24 = 84\). 2. For b), \(18 \times 4 = 20 \times 4 - 2 \times 4 = 80 - 8 = 72\). 3. For c), \(23 \times 3 = 20 \times 3 + 3 \times 3 = 60 + 9 = 69\).

Answer

a) \(10 \times 6 + 4 \times 6 = 60 + 24 = 84\) b) \(20 \times 4 - 2 \times 4 = 80 - 8 = 72\) c) \(20 \times 3 + 3 \times 3 = 60 + 9 = 69\)
5205194
a) Find the sum \(156 + 156 + 156 + 156\). b) Write the related multiplication expression. c) Solve the multiplication using partial products. Break \(156\) into hundreds, tens, and ones, then add the partial products.

Hints

- Count how many times \(156\) appears in the sum. - Break \(156\) into hundreds, tens, and ones. - Find and add the partial products.

Solution

1. Add the four equal addends: \(156 + 156 + 156 + 156 = 624\). 2. Since \(156\) is added four times, the multiplication expression is \(4 \times 156\). 3. Find the partial products: \(4 \times 100 = 400\), \(4 \times 50 = 200\), and \(4 \times 6 = 24\). 4. Add: \(400 + 200 + 24 = 624\).

Answer

a) \(624\) b) \(4 \times 156\) c) \(400 + 200 + 24 = 624\)
5205204
a) Write \(8 \times 125\) as repeated addition with equal addends. b) Find the product by completing these partial products: \(8 \times 100 = \dots\) \(8 \times 20 = \dots\) \(8 \times 5 = \dots\) Then add the three partial products.

Hints

- The factor \(8\) tells how many equal addends to write. - Break \(125\) into hundreds, tens, and ones. - Add the three partial products carefully.

Solution

1. The repeated addition is \(125 + 125 + 125 + 125 + 125 + 125 + 125 + 125\). 2. The partial products are \(8 \times 100 = 800\), \(8 \times 20 = 160\), and \(8 \times 5 = 40\). 3. Add: \(800 + 160 + 40 = 1000\).

Answer

a) \(125 + 125 + 125 + 125 + 125 + 125 + 125 + 125\) b) \(800 + 160 + 40 = 1000\)
5205804
a) Write an addition expression in which \(132\) appears as an addend six times. b) Find \(6 \times 132\) using partial products. Break \(132\) into place-value parts.

Hints

- The factor \(6\) tells how many equal addends to write. - Break \(132\) into hundreds, tens, and ones. - Multiply each part by \(6\), then add.

Solution

1. The repeated addition is \(132 + 132 + 132 + 132 + 132 + 132\). 2. Break apart \(132\) as \(100 + 30 + 2\). 3. Find the partial products: \(6 \times 100 = 600\), \(6 \times 30 = 180\), and \(6 \times 2 = 12\). 4. Add: \(600 + 180 + 12 = 792\).

Answer

a) \(132 + 132 + 132 + 132 + 132 + 132\) b) \(6 \times 132 = 792\)
5209064
Which two expressions have the same value? Show your work using partial products. A) \(140 \times 6\) B) \(190 \times 4\) C) \(280 \times 3\)

Hints

- Break each three-digit factor into hundreds and tens. - Find and add the partial products. - Compare the three final products.

Solution

1. For A, \(100 \times 6 = 600\) and \(40 \times 6 = 240\). Then \(600 + 240 = 840\). 2. For B, \(100 \times 4 = 400\) and \(90 \times 4 = 360\). Then \(400 + 360 = 760\). 3. For C, \(200 \times 3 = 600\) and \(80 \times 3 = 240\). Then \(600 + 240 = 840\). 4. Expressions A and C have the same value.

Answer

A and C have the same value, \(840\).
5209194
Leo used partial products to solve \(47 \times 8\): \(40 \times 8 = 320\) \(7 \times 8 = 48\) \(320 + 48 = 368\) Check Leo’s work. Identify the error and find the correct product.

Hints

- Check each line of Leo’s work separately. - Verify both basic multiplication facts. - Add the corrected partial products.

Solution

1. The first partial product, \(40 \times 8 = 320\), is correct. 2. The second partial product is incorrect: \(7 \times 8 = 56\), not \(48\). 3. Add the correct partial products: \(320 + 56 = 376\).

Answer

Leo’s error is the second partial product. \(7 \times 8 = 56\), not \(48\). The correct product is \(376\).
5209344
Find \(156 \times 4\) by multiplying the hundreds, tens, and ones separately. How much less is the product than \(1000\)?

Hints

- Break \(156\) into hundreds, tens, and ones. - Multiply each part by \(4\), then add. - Subtract the product from \(1000\) to find the difference.

Solution

1. Break apart \(156\) as \(100 + 50 + 6\). 2. Find the partial products: \(100 \times 4 = 400\), \(50 \times 4 = 200\), and \(6 \times 4 = 24\). 3. Add: \(400 + 200 + 24 = 624\). 4. Find the difference: \(1000 - 624 = 376\).

Answer

The product is \(624\). It is \(376\) less than \(1000\).
5209354
Find and compare the products. Write \(<\), \(>\), or \(=\) in each box. a) \(135 \times 3 \square 112 \times 4\) b) \(160 \times 5 \square 198 \times 4\)

Hints

- Find both products in each part. - Use partial products to make the multiplication easier. - Compare the final values.

Solution

1. For part a, \(135 \times 3 = 405\) and \(112 \times 4 = 448\), so \(405 < 448\). 2. For part b, \(160 \times 5 = 800\) and \(198 \times 4 = 792\), so \(800 > 792\).

Answer

a) \(135 \times 3 < 112 \times 4\) b) \(160 \times 5 > 198 \times 4\)
5210314
Compare the products. Write \(<\), \(>\), or \(=\) in each box. a) \(104 \times 7 \square 107 \times 4\) b) \(120 \times 8 \square 160 \times 6\) c) \(150 \times 4 \square 130 \times 5\)

Hints

- Estimate first, then calculate both products. - Use partial products if needed. - Compare the final values.

Solution

1. For part a, \(104 \times 7 = 728\) and \(107 \times 4 = 428\), so \(728 > 428\). 2. For part b, \(120 \times 8 = 960\) and \(160 \times 6 = 960\), so the products are equal. 3. For part c, \(150 \times 4 = 600\) and \(130 \times 5 = 650\), so \(600 < 650\).

Answer

a) \(104 \times 7 > 107 \times 4\) b) \(120 \times 8 = 160 \times 6\) c) \(150 \times 4 < 130 \times 5\)
5210384
Use partial products to solve and compare the two problems. Problem A: \(47 \times 6\) Problem B: \(32 \times 9\) Which product is greater? What is the difference between the products?

Hints

- Find both products using partial products. - Compare the two results. - Subtract the smaller product from the larger product.

Solution

1. For Problem A, \(40 \times 6 = 240\) and \(7 \times 6 = 42\). Then \(240 + 42 = 282\). 2. For Problem B, \(30 \times 9 = 270\) and \(2 \times 9 = 18\). Then \(270 + 18 = 288\). 3. Since \(288 > 282\), Problem B has the greater product. 4. The difference is \(288 - 282 = 6\).

Answer

Problem B has the greater product: \(288\) compared with \(282\). The difference is \(6\).
5210434
Compare the values. Write \(<\), \(>\), or \(=\) in each box. a) \(120 \times 4 \square 110 \times 5\) b) \(7 \times 60 \square 400\) c) \(250 \times 2 \square 100 \times 5\) d) \(9 \times 30 \square 280\) e) \(80 \times 4 \square 3 \times 110\)

Hints

- Find the value on each side of the box. - Use place-value parts to simplify the multiplication. - Compare the final values.

Solution

1. For part a, \(120 \times 4 = 480\) and \(110 \times 5 = 550\), so \(480 < 550\). 2. For part b, \(7 \times 60 = 420\), so \(420 > 400\). 3. For part c, \(250 \times 2 = 500\) and \(100 \times 5 = 500\), so the values are equal. 4. For part d, \(9 \times 30 = 270\), so \(270 < 280\). 5. For part e, \(80 \times 4 = 320\) and \(3 \times 110 = 330\), so \(320 < 330\).

Answer

a) \(<\) b) \(>\) c) \(=\) d) \(<\) e) \(<\)
5210444
Find the three products. Compare them and describe what you notice. a) \(124 \times 4\) b) \(248 \times 2\) c) \(62 \times 8\)

Hints

- Find each product separately. - Use partial products for the larger factors. - Compare the three final values.

Solution

1. For part a, \(100 \times 4 = 400\), \(20 \times 4 = 80\), and \(4 \times 4 = 16\). Then \(400 + 80 + 16 = 496\). 2. For part b, \(200 \times 2 = 400\), \(40 \times 2 = 80\), and \(8 \times 2 = 16\). Then \(400 + 80 + 16 = 496\). 3. For part c, \(60 \times 8 = 480\) and \(2 \times 8 = 16\). Then \(480 + 16 = 496\). 4. All three products are equal.

Answer

a) \(496\) b) \(496\) c) \(496\) All three products are equal.
5212044
A school fundraiser sells \(45\) raffle tickets. Each ticket costs \(\$8\). 1. How much do \(40\) tickets cost? 2. How much do the remaining \(5\) tickets cost? 3. What is the total cost of all \(45\) tickets? Explain how the first two answers give the total.

Hints

- Find the cost of the first \(40\) tickets. - Find the cost of the remaining \(5\) tickets. - Add the two costs.

Solution

1. Find the cost of \(40\) tickets: \(40 \times 8 = 320\), so the cost is \(\$320\). 2. Find the cost of \(5\) tickets: \(5 \times 8 = 40\), so the cost is \(\$40\). 3. Add the two partial costs: \(\$320 + \$40 = \$360\). 4. Because \(40 + 5 = 45\), the costs of those two groups combine to give the cost of all \(45\) tickets.

Answer

1. \(40\) tickets cost \(\$320\). 2. \(5\) tickets cost \(\$40\). 3. All \(45\) tickets cost \(\$360\). Add the first two costs because \(40 + 5 = 45\).
5212864
Solve each problem. In the last part, compare the products. a) \(145 \times 6\) b) \(260 \times 3\) c) \(312 \times 3\) d) \(108 \times 7\) e) Which product is greater: \(160 \times 4\) or \(210 \times 3\)?

Hints

- Break each three-digit factor into place-value parts. - Add the partial products carefully. - For part e, find both products before comparing.

Solution

1. For part a, \(100 \times 6 = 600\), \(40 \times 6 = 240\), and \(5 \times 6 = 30\). Then \(600 + 240 + 30 = 870\). 2. For part b, \(200 \times 3 = 600\) and \(60 \times 3 = 180\). Then \(600 + 180 = 780\). 3. For part c, \(300 \times 3 = 900\), \(10 \times 3 = 30\), and \(2 \times 3 = 6\). Then \(900 + 30 + 6 = 936\). 4. For part d, \(100 \times 7 = 700\) and \(8 \times 7 = 56\). Then \(700 + 56 = 756\). 5. For part e, \(160 \times 4 = 640\) and \(210 \times 3 = 630\), so \(640 > 630\).

Answer

a) \(870\) b) \(780\) c) \(936\) d) \(756\) e) \(160 \times 4\) is greater.
5213684
Find each product and match the expressions that have the same value. \(40 \times 8 = \dots\) \(140 \times 3 = \dots\) \(500 \times 2 = \dots\) \(160 \times 2 = \dots\) \(70 \times 6 = \dots\) \(250 \times 4 = \dots\)

Hints

- Find all six products first. - Look for factor pairs related by doubling one factor and halving the other. - Match equal results.

Solution

1. The products are \(40 \times 8 = 320\), \(140 \times 3 = 420\), \(500 \times 2 = 1000\), \(160 \times 2 = 320\), \(70 \times 6 = 420\), and \(250 \times 4 = 1000\). 2. The equal pairs are \(40 \times 8\) and \(160 \times 2\); \(140 \times 3\) and \(70 \times 6\); and \(500 \times 2\) and \(250 \times 4\).

Answer

\(40 \times 8 = 320\) and \(160 \times 2 = 320\) \(140 \times 3 = 420\) and \(70 \times 6 = 420\) \(500 \times 2 = 1000\) and \(250 \times 4 = 1000\)
5213694
Compare the products. Write \(<\), \(>\), or \(=\) in each box. a) \(120 \times 4 \square 60 \times 8\) b) \(150 \times 3 \square 110 \times 4\) c) \(210 \times 2 \square 80 \times 5\) d) \(130 \times 3 \square 100 \times 4\)

Hints

- Find the product on each side. - Record the intermediate results if helpful. - Choose the comparison symbol that makes each statement true.

Solution

1. For part a, \(120 \times 4 = 480\) and \(60 \times 8 = 480\), so the products are equal. 2. For part b, \(150 \times 3 = 450\) and \(110 \times 4 = 440\), so \(450 > 440\). 3. For part c, \(210 \times 2 = 420\) and \(80 \times 5 = 400\), so \(420 > 400\). 4. For part d, \(130 \times 3 = 390\) and \(100 \times 4 = 400\), so \(390 < 400\).

Answer

a) \(120 \times 4 = 60 \times 8\) b) \(150 \times 3 > 110 \times 4\) c) \(210 \times 2 > 80 \times 5\) d) \(130 \times 3 < 100 \times 4\)
5214444
Find each product. Which expressions have the same value? a) \(120 \times 4\) b) \(160 \times 3\) c) \(240 \times 2\) d) \(110 \times 4\) e) \(220 \times 2\)

Hints

- Find each product separately. - Compare the five results. - Group expressions with matching products.

Solution

1. The products are \(120 \times 4 = 480\), \(160 \times 3 = 480\), \(240 \times 2 = 480\), \(110 \times 4 = 440\), and \(220 \times 2 = 440\). 2. Parts a, b, and c have the same value. Parts d and e have the same value.

Answer

a), b), and c) each equal \(480\). d) and e) each equal \(440\).
5214454
Complete each partial-products method. a) \(132 \times 3\) \(100 \times 3 = \dots\) \(30 \times 3 = \dots\) \(2 \times 3 = \dots\) Product: \(\dots\) b) \(205 \times 4\) \(200 \times 4 = \dots\) \(0 \times 4 = \dots\) \(5 \times 4 = \dots\) Product: \(\dots\) c) \(3 \times 210\) \(3 \times 200 = \dots\) \(3 \times 10 = \dots\) Product: \(\dots\)

Hints

- Break the larger factor into hundreds, tens, and ones. - Multiply each place-value part by the one-digit factor. - Add the partial products. - In part b, account for the zero in the tens place.

Solution

1. For part a, \(100 \times 3 = 300\), \(30 \times 3 = 90\), and \(2 \times 3 = 6\). Then \(300 + 90 + 6 = 396\). 2. For part b, \(200 \times 4 = 800\), \(0 \times 4 = 0\), and \(5 \times 4 = 20\). Then \(800 + 0 + 20 = 820\). 3. For part c, \(3 \times 200 = 600\) and \(3 \times 10 = 30\). Then \(600 + 30 = 630\).

Answer

a) \(300\), \(90\), \(6\); product: \(396\) b) \(800\), \(0\), \(20\); product: \(820\) c) \(600\), \(30\); product: \(630\)
5214604
Fill in the missing numbers in each partial-products method. a) \(68 \times 4 = \dots\) \(60 \times 4 = \dots\) \(8 \times 4 = \dots\) Product: \(\dots\) b) \(43 \times 7 = \dots\) \(\dots \times 7 = 280\) \(\dots \times 7 = 21\) Product: \(\dots\)

Hints

- Identify the tens and ones parts of each two-digit factor. - Determine which missing factor produces each stated partial product. - For \(280\), think about which number multiplied by \(7\) gives that product. - Add the partial products.

Solution

1. For part a, \(60 \times 4 = 240\) and \(8 \times 4 = 32\). Then \(240 + 32 = 272\). 2. For part b, \(43\) is broken into \(40 + 3\). Then \(40 \times 7 = 280\), \(3 \times 7 = 21\), and \(280 + 21 = 301\).

Answer

a) \(68 \times 4 = 272\), \(60 \times 4 = 240\), \(8 \times 4 = 32\), and the product is \(272\). b) \(43 \times 7 = 301\), \(40 \times 7 = 280\), \(3 \times 7 = 21\), and the product is \(301\).
5215474
Find each product using partial products. a) \(13 \times 4\) b) \(26 \times 4\) c) \(15 \times 3\) d) \(30 \times 3\) What happens to the product when the first factor is doubled?

Hints

- Break each two-digit factor into tens and ones. - Add the partial products for each problem. - Compare parts a and b, then parts c and d. - Check how both the factor and the product change.

Solution

1. For part a, \(10 \times 4 = 40\) and \(3 \times 4 = 12\). Then \(40 + 12 = 52\). 2. For part b, \(20 \times 4 = 80\) and \(6 \times 4 = 24\). Then \(80 + 24 = 104\). 3. For part c, \(10 \times 3 = 30\) and \(5 \times 3 = 15\). Then \(30 + 15 = 45\). 4. For part d, \(30 \times 3 = 90\). 5. Since \(26\) is twice \(13\), \(104\) is twice \(52\). Since \(30\) is twice \(15\), \(90\) is twice \(45\). When one factor is doubled and the other factor stays the same, the product doubles.

Answer

a) \(52\) b) \(104\) c) \(45\) d) \(90\) When the first factor is doubled, the product doubles.
5363144
Complete this product wall. Each upper brick is the product of the two bricks directly below it.
Figure for problem 536314

Hints

- Begin with a connected group that has only one unknown value. - Use division when a product and one factor are known.

Solution

1. The left brick in the second row is \(2 \times 1 = 2\). 2. For the missing bottom value, solve \(1 \times x = 3\), so \(x = 3\). 3. The right brick in the second row is \(3 \times 2 = 6\). 4. The third row is \(2 \times 3 = 6\) and \(3 \times 6 = 18\). 5. The top is \(6 \times 18 = 108\).

Answer

Bottom row: \(2\), \(1\), \(3\), \(2\) Second row: \(2\), \(3\), \(6\) Third row: \(6\), \(18\) Top: \(108\)
5373754
A bookcase has \(5\) rows with \(12\) books in each row. Four books are borrowed from each row. How many books remain? Solve in two ways.
Figure for problem 537375

Hints

- You can find the number remaining in each row first. - Or find the total number of books and subtract all the borrowed books. - Both methods should give the same result.

Solution

1. Find the number left in each row, then multiply: \(5 \times (12 - 4) = 5 \times 8 = 40\). 2. Or subtract all borrowed books from the original total: \(5 \times 12 - 5 \times 4 = 60 - 20 = 40\).

Answer

\(40\) books remain. Two methods are \(5 \times (12 - 4) = 40\) and \(5 \times 12 - 5 \times 4 = 40\).

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