Aimathic
Login | English | Deutsch

Grade 5 math worksheets

Build your own math worksheets from 35,000+ problems for grades 3 to 12, from fractions to AP Calculus. Every problem comes with step-by-step solutions.

Fraction × whole number interpretation

Learning goals

  • Interprets a fraction times a whole number as repeated addition or scaling.
  • Represents the product with models or equations.
  • Computes products of fractions and whole numbers.
  • Interprets the result in context.

Click problems to add them to your worksheet.

Fraction × whole number interpretation 1
On this line, each curved arrow is a jump. What multiplication expression, with the fraction first, represents all four jumps?
Figure for problem 558961

Hints

- Count the curved arrows. - Use the fraction equivalent of the jump label. - The whole-number factor tells how many equal jumps are used.

Solution

1. One jump is \(\frac{2}{5}\). 2. The picture shows \(4\) equal jumps. 3. Four copies of \(\frac{2}{5}\) are represented by \(\frac{2}{5}\times4\).

Answer

\(\frac{2}{5}\times4\)
Fraction × whole number interpretation 2
Which multiplication expression matches \(\frac{1}{6}+\frac{1}{6}+\frac{1}{6}\)? A) \(\frac{1}{6}\times3\) B) \(\frac{1}{6}\times6\) C) \(\frac{3}{6}\times6\) Choose the expression and find its value.

Hints

- Count the number of equal fractional addends. - The whole-number factor tells how many copies of the fraction are used. - Simplify the fraction after adding.

Solution

1. The sum has three copies of \(\frac{1}{6}\), so it matches \(\frac{1}{6}\times3\). 2. \(\frac{1}{6}+\frac{1}{6}+\frac{1}{6}=\frac{3}{6}=\frac{1}{2}\).

Answer

A) \(\frac{1}{6}\times3=\frac{1}{2}\).
Fraction × whole number interpretation 3
The whole bar represents \(12\,\text{feet}\). Which expression gives the shaded length? A) \(\frac{3}{4}\times12\) B) \(\frac{1}{4}\times12\) C) \(12\div\frac{3}{4}\)
Figure for problem 558963

Hints

- Read the shaded fraction from the bar. - Ask which expression means that fraction of the full length. - You do not need to calculate the length.

Solution

1. The bar has \(4\) equal parts and \(3\) are shaded, so the shaded part is \(\frac{3}{4}\) of the whole. 2. Therefore the shaded length is represented by \(\frac{3}{4}\times12\).

Answer

A) \(\frac{3}{4}\times12\).
Fraction × whole number interpretation 4
A water cooler contains \(6\) gallons of water. A team uses \(\frac{3}{4}\) of the water. Explain how \(\frac{3}{4}\times6\) can be found by first dividing \(6\) into \(4\) equal parts and then taking \(3\) of those parts. How many gallons are used?

Hints

- The denominator tells how many equal parts to split the whole-number amount into. - After finding one equal part, use the numerator to decide how many of those parts to take. - Keep the gallon unit attached to the quantity being partitioned.

Solution

1. Divide the \(6\) gallons into \(4\) equal parts: \(6\div4=\frac{3}{2}\) gallons in each part. 2. Take \(3\) of those equal parts: \(3\times\frac{3}{2}=\frac{9}{2}\) gallons. 3. \(\frac{9}{2}=4\frac{1}{2}\), so \(4\frac{1}{2}\) gallons are used.

Answer

\(4\frac{1}{2}\) gallons are used.
Fraction × whole number interpretation 5
Use the model to find \(\frac{3}{4}\times12\). Explain how the denominator and numerator determine the selected number of tiles.
Figure for problem 540850

Hints

- Let the denominator tell you how many equal groups to make. - Then use the numerator to decide how many of those groups to take.

Solution

1. Divide \(12\) tiles into \(4\) equal groups: each group has \(3\) tiles. 2. Take \(3\) groups: \(3\times3=9\) tiles.

Answer

\(9\) tiles are selected.
Fraction × whole number interpretation 6
Use the model to find \(\frac{2}{5}\times15\). Explain how the denominator and numerator determine the selected number of counters.
Figure for problem 540860

Hints

- Use the denominator to decide how many equal groups the set needs. - Use the numerator to decide how many groups count toward the product.

Solution

1. Partition \(15\) counters into \(5\) equal groups: \(15\div5=3\) counters per group. 2. Select \(2\) groups: \(2\times3=6\) counters.

Answer

\(6\) counters are selected.
Fraction × whole number interpretation 7
Use the model to represent \(\frac{4}{7}\times21\). Explain how the denominator and numerator determine the selected number of cards.
Figure for problem 540869

Hints

- Let the denominator tell you how many equal groups to make. - Then use the numerator to decide how many groups are included.

Solution

1. The denominator \(7\) partitions \(21\) cards into \(7\) equal groups of \(3\). 2. The numerator \(4\) selects \(4\) groups. 3. \(4\times3=12\) cards are selected.

Answer

\(12\) cards are selected.
Fraction × whole number interpretation 8
Use the model to explain why \(\frac{5}{8}\times24\) can be found by dividing first and then taking equal groups. Find the product.
Figure for problem 540878

Hints

- Interpret the denominator as a number of equal groups. - Interpret the numerator as the number of groups to use.

Solution

1. The denominator \(8\) partitions \(24\) into \(8\) equal parts: \(24\div8=3\). 2. The numerator \(5\) selects \(5\) of those parts: \(5\times3=15\). 3. Therefore \(\frac{5}{8}\times24=15\).

Answer

\(15\)
Fraction × whole number interpretation 9
Use the model to find \(\frac{7}{12}\times36\). Explain how the denominator and numerator guide the grouping.
Figure for problem 540903

Hints

- Use the denominator to decide the number of equal groups. - Use the numerator to decide how many groups are selected.

Solution

1. Divide \(36\) objects into \(12\) equal groups: each group has \(3\) objects. 2. Take \(7\) groups: \(7\times3=21\).

Answer

\(21\) objects.
Fraction × whole number interpretation 10
Amina calculates \(\frac{5}{6}\times18\) as \((5\times18)\div6\). Explain why this matches the meaning of \(\frac{5}{6}\) of \(18\), then find the product.

Hints

- Interpret the denominator as the number of equal parts in the whole-number amount. - Interpret the numerator as the number of those equal parts being taken. - Compare those roles with the order of multiplication and division in the proposed expression.

Solution

1. Taking \(\frac{5}{6}\) of \(18\) means partitioning \(18\) into \(6\) equal parts and taking \(5\) parts. 2. Multiplying by \(5\) and dividing by \(6\) gives the same amount: \((5\times18)\div6=15\). 3. Therefore \(\frac{5}{6}\times18=15\).

Answer

The expression works because multiplying by \(5\) counts five copies and dividing by \(6\) makes each copy one sixth of the original amount. Thus, \(\frac{5}{6}\times18=15\).
Fraction × whole number interpretation 11
Use the model to find \(\frac{3}{7}\times28\). Explain how the denominator and numerator determine the selected number of counters.
Figure for problem 540952

Hints

- Use the denominator to determine the number of equal groups. - Use the numerator to determine how many groups to select.

Solution

1. Because \(28=7\times4\), one seventh of the \(28\) counters is \(4\) counters. 2. Three sevenths is three groups of \(4\), so \(3\times4=12\) counters are selected. 3. Therefore \(\frac{3}{7}\times28=12\).

Answer

\(12\) counters.
Fraction × whole number interpretation 12
Use the model to explain the meaning of \(\frac{5}{6}\times30\), then find the product.
Figure for problem 540960

Hints

- Use the denominator to decide how many equal groups the whole collection should form. - After finding one equal group, think about what the numerator tells you to select.

Solution

1. Partition the \(30\) counters into \(6\) equal groups, so each group has \(30\div6=5\) counters. 2. The numerator \(5\) means take \(5\) of those groups. 3. The selected amount is \(5\times5=25\) counters.

Answer

\(\frac{5}{6}\times30=25\).
Fraction × whole number interpretation 13
Use the model to explain \(\frac{4}{9}\times45\) in the context of a \(45\)-minute practice session, then find the number of minutes used for skill stations.
Figure for problem 540968

Hints

- Let the denominator tell you how many equal groups to make from the total time. - Then use the numerator to decide how many of those groups belong to the selected part.

Solution

1. Split \(45\) minutes into \(9\) equal groups: \(45\div9=5\) minutes per group. 2. Take \(4\) of those groups: \(4\times5=20\). 3. Therefore \(\frac{4}{9}\times45=20\).

Answer

The skill stations use \(20\) minutes.
Fraction × whole number interpretation 14
Use the two models to compare \(\frac{2}{3}\times30\) with \(\frac{4}{6}\times30\). Explain why the equivalent fractions lead to the same selected number of objects, then find that number.
Figure for problem 541013

Hints

- First compare the two fraction multipliers themselves. - Think about whether equivalent fractions select the same portion of one fixed whole collection. - Use one convenient grouping to find the selected amount.

Solution

1. For \(\frac{2}{3}\times30\), divide \(30\) into \(3\) equal groups of \(10\), then take \(2\) groups: \(20\). 2. For \(\frac{4}{6}\times30\), divide \(30\) into \(6\) equal groups of \(5\), then take \(4\) groups: \(20\). 3. The fractions \(\frac{2}{3}\) and \(\frac{4}{6}\) are equivalent, so they select the same portion of the collection.

Answer

Both products equal \(20\).
Fraction × whole number interpretation 15
Which statement correctly interprets \(\frac{5}{12}\times36\)? a) Divide \(36\) into \(12\) equal groups and take \(5\) groups. b) Divide \(36\) into \(5\) equal groups and take \(12\) groups. Choose the correct interpretation and find the product.
Figure for problem 541064

Hints

- Count the equal rows in the model and connect them to the denominator. - What does the numerator tell you to do with those equal groups? - Use the size of one group to find the selected amount.

Solution

1. The denominator \(12\) tells how many equal groups the whole amount is partitioned into, so a) is correct. 2. Each group has \(36\div12=3\) objects. 3. Take \(5\) groups: \(5\times3=15\). 4. Therefore \(\frac{5}{12}\times36=15\).

Answer

a) is correct, and the product is \(15\).
Fraction × whole number interpretation 16
Use the model to explain why \(\frac{3}{5}\times40\) can be written as \(3\times(40\div5)\), then find the product.
Figure for problem 541096

Hints

- Let the denominator determine the equal partition of the whole amount. - Let the numerator determine how many equal groups are selected. - Translate those two roles into operations in the same order.

Solution

1. The denominator \(5\) means divide the \(40\) objects into \(5\) equal groups: \(40\div5=8\). 2. The numerator \(3\) means take \(3\) of those groups. 3. Thus \(\frac{3}{5}\times40=3\times8=24\).

Answer

\(\frac{3}{5}\times40=3\times(40\div5)=24\).
Fraction × whole number interpretation 17
Use the model to explain \(\frac{7}{9}\times54\) and find the selected number of items.
Figure for problem 541105

Hints

- Use the denominator to decide how many equal groups the collection should form. - Find the size of one group before using the numerator. - The numerator tells how many of those equal groups are selected.

Solution

1. Divide \(54\) into \(9\) equal groups: \(54\div9=6\) items per group. 2. Select \(7\) groups: \(7\times6=42\). 3. Therefore \(\frac{7}{9}\times54=42\).

Answer

\(42\) items are selected.
Fraction × whole number interpretation 18
A workshop lasts \(40\) minutes and uses \(\frac{7}{8}\) of its time for activities. Use the model to explain the fraction of the total and find the number of activity minutes.
Figure for problem 541120

Hints

- Use the denominator to decide how many equal groups to make from the total time. - Find the size of one group before using the numerator. - The numerator tells how many equal time groups are included.

Solution

1. The denominator \(8\) means to divide the \(40\) minutes into \(8\) equal groups. 2. Each group has \(40\div8=5\) minutes. 3. The numerator \(7\) means to select \(7\) of those groups: \(7\times5=35\). 4. Therefore \(\frac{7}{8}\times40=35\).

Answer

The activities use \(35\) minutes.
Fraction × whole number interpretation 19
Each whole bar represents \(8\) counters. The colored quarter-parts show how much of that \(8\)-counter amount is selected. What improper-fraction multiplier is represented, and how many counters are selected altogether?
Figure for problem 554447

Hints

- Use the number of equal parts in one whole to identify the denominator of the multiplier. - Count the colored parts across both wholes to identify the numerator. - Determine the number of counters represented by one equal part before combining the colored parts.

Solution

1. Each whole is divided into \(4\) equal parts, so each colored part represents one fourth of \(8\), or \(2\) counters. 2. The model colors \(7\) quarter-parts, so the multiplier is \(\frac{7}{4}\). 3. Seven groups of \(2\) counters make \(14\) counters, so \(\frac{7}{4}\times8=14\).

Answer

The multiplier is \(\frac{7}{4}\), and \(\frac{7}{4}\times8=14\) counters.
Fraction × whole number interpretation 20
Maya and Owen explain \(\frac{3}{4}\times4\). Maya says it is four copies of \(\frac{3}{4}\): \(\frac{3}{4}+\frac{3}{4}+\frac{3}{4}+\frac{3}{4}\). Owen says it is \(\frac{3}{4}\) of \(4\). Show that both interpretations give the same product.

Hints

- For the repeated-addition view, add four equal fractions. - For the scaling view, find one fourth of \(4\) first. - Compare the two results rather than treating the explanations as different operations.

Solution

1. Maya's repeated addition gives \(\frac{12}{4}=3\). 2. For Owen's scaling view, one fourth of \(4\) is \(1\), so three fourths of \(4\) is \(3\). 3. Both interpretations give \(\frac{3}{4}\times4=3\).

Answer

Both interpretations give \(3\): \(\frac{3}{4}+\frac{3}{4}+\frac{3}{4}+\frac{3}{4}=3\) and \(\frac{3}{4}\) of \(4\) is \(3\).
Fraction × whole number interpretation 21
Each bar represents one whole. Write a multiplication equation with a unit fraction and a whole-number factor for the shaded amount. Give the shaded total as a fraction and explain what the whole-number factor counts.
Figure for problem 558965

Hints

- Look at one bar to name the size of one small part. - Count the shaded small parts across both bars. - Use that count as the whole-number factor.

Solution

1. Each bar is split into \(5\) equal parts, so one small part is \(\frac{1}{5}\) of a whole. 2. There are \(7\) shaded one-fifth parts. 3. Seven copies of \(\frac{1}{5}\) give \(\frac{1}{5}\times7=\frac{7}{5}\). 4. The factor \(7\) counts the shaded one-fifth parts.

Answer

\(\frac{1}{5}\times7=\frac{7}{5}\). The factor \(7\) counts the shaded one-fifth parts.
Fraction × whole number interpretation 22
Which expressions are equal to \(\frac{3}{5}\times20\)? Select all that apply and explain. A) \(3\times(20\div5)\) B) \((3\times20)\div5\) C) \((20\div3)\times5\)

Hints

- Think about the roles of the numerator and denominator in the fraction. - Test whether each expression partitions into fifths and selects three of those parts.

Solution

1. \(\frac{3}{5}\times20\) means divide \(20\) into \(5\) equal parts and take \(3\), so A is equivalent. 2. Multiplying \(20\) by \(3\) and then dividing by \(5\) gives the same value, so B is equivalent. 3. C divides by \(3\) and multiplies by \(5\), reversing the roles of numerator and denominator.

Answer

A and B are equal to \(\frac{3}{5}\times20\).
Fraction × whole number interpretation 23
Use the model to create a short story situation represented by \(\frac{7}{10}\times30\). In your story, explain what \(30\), \(10\), and \(7\) represent, then find the product.
Figure for problem 540893

Hints

- Choose a whole-number collection that can naturally be partitioned into ten equal groups. - Make the numerator describe how many of those equal groups are selected. - Check that your story leads to the same multiplication expression.

Solution

1. One valid story is: A display has \(30\) photos, and \(\frac{7}{10}\) of them are landscape photos. 2. Partition \(30\) into \(10\) equal groups: \(30\div10=3\). 3. Take \(7\) groups: \(7\times3=21\).

Answer

Answers will vary. A valid story must identify \(30\) as the whole collection, partition it into \(10\) equal groups, select \(7\) groups, and give the product \(21\).
Fraction × whole number interpretation 24
Use the model to explain \(\frac{7}{4}\times8\), including why the result can be greater than \(8\). The left block represents the original set of \(8\); the extension to the right shows additional equal fourth-groups. Find the product.
Figure for problem 540911

Hints

- Identify how many equal groups make the original whole set. - Use the numerator to determine how many of those equal-sized groups are selected altogether. - Compare the number of selected groups with the number of groups in one whole set.

Solution

1. The original \(8\) objects are partitioned into \(4\) equal groups, so each fourth-group contains \(8\div4=2\) objects. 2. The model extends to show \(7\) such groups altogether. Taking \(7\) groups gives \(7\times2=14\). 3. Because \(\frac{7}{4}>1\), the model must extend beyond the original \(4\) groups, so a product greater than \(8\) is reasonable.

Answer

\(\frac{7}{4}\times8=14\). The product is greater than \(8\) because \(\frac{7}{4}\) selects seven fourth-groups, which is three groups more than one whole set.
Fraction × whole number interpretation 25
Find \(\frac{9}{5}\times10\) by interpreting the fraction as \(9\) parts when \(10\) is partitioned into \(5\) equal parts. Explain why a fraction greater than \(1\) can select more than one whole amount.

Hints

- Use the denominator to find the size of one equal part of \(10\). - The numerator may count more parts than make one whole when the fraction is improper.

Solution

1. Partition \(10\) into \(5\) equal parts: each part is \(2\). 2. Take \(9\) parts: \(9\times2=18\). 3. Since \(\frac{9}{5}=1\frac{4}{5}\), the multiplier represents one whole amount plus four fifths more.

Answer

\(18\)
Fraction × whole number interpretation 26
A section has \(40\) seats, and \(\frac{3}{8}\) are reserved. Explain two equivalent calculation orders for \(\frac{3}{8}\times40\): divide by \(8\) then multiply by \(3\), or multiply by \(3\) then divide by \(8\). Find the number of reserved seats.

Hints

- The denominator controls how the whole-number quantity is partitioned. - The numerator controls how many equal parts are taken. - Check whether both calculation orders preserve those roles.

Solution

1. Partition first: \(40\div8=5\), then \(5\times3=15\). 2. Multiply first: \(40\times3=120\), then \(120\div8=15\). 3. Both orders represent taking \(3\) of \(8\) equal parts of \(40\).

Answer

\(15\) seats are reserved.
Fraction × whole number interpretation 27
Find \(\frac{11}{6}\times12\) by partitioning \(12\) into \(6\) equal parts and taking \(11\) parts. Explain the interpretation.

Hints

- The denominator tells how many equal parts to make from \(12\). - The numerator tells how many parts to count, even when that is more than one whole set.

Solution

1. Partition \(12\) into \(6\) equal parts: each part is \(2\). 2. Take \(11\) parts: \(11\times2=22\). 3. The improper fraction \(\frac{11}{6}\) represents more than one full set of six parts, so the product is greater than \(12\).

Answer

\(22\)
Fraction × whole number interpretation 28
Solve \(\frac{a}{6}\times30=20\). Find \(a\) and explain what the numerator means.
Figure for problem 540988

Hints

- Count the equal rows in the model to connect the picture with sixths. - Find how many objects are in one row. - Compare \(20\) with one row to decide how many rows are selected.

Solution

1. Divide the \(30\) tokens into \(6\) equal groups: \(30\div6=5\) tokens per group. 2. To select \(20\) tokens, the number of groups must satisfy \(a\times5=20\), so \(a=4\). 3. The numerator \(4\) means selecting \(4\) of the \(6\) equal groups.

Answer

\(a=4\), so the fraction is \(\frac{4}{6}\). The numerator tells how many of the six equal groups are selected.
Fraction × whole number interpretation 29
Leila wants to find \(\frac{3}{8}\times24\). She divides the \(24\) objects into \(4\) equal groups and takes \(3\) groups. Explain why this does not represent \(\frac{3}{8}\) of \(24\). Then show the correct grouping and find the product.

Hints

- What do the \(3\) and the \(8\) each tell you about the equal groups? - Check whether Leila's \(4\) groups match the fraction she is using. - After deciding how many equal groups the whole should have, decide how many of those groups to take.

Solution

1. The denominator \(8\) tells how many equal groups the \(24\) objects should be split into. Leila made \(4\) groups instead of \(8\). 2. Divide \(24\) into \(8\) equal groups: \(24\div8=3\) objects per group. 3. Take \(3\) groups because the numerator is \(3\): \(3\times3=9\). 4. Therefore \(\frac{3}{8}\times24=9\).

Answer

Leila should make \(8\) equal groups and take \(3\) of them. The product is \(9\).
Fraction × whole number interpretation 30
Use the two models to compare \(\frac{4}{5}\times20\) and \(\frac{5}{4}\times20\). In model a), the selected part lies within the original \(20\). In model b), the left block is the original \(20\) and the rightmost column is the additional fourth-group. Explain how each fraction changes the original amount, then find both products.
Figure for problem 541005

Hints

- In each model, identify how many equal groups make one original whole amount. - Use the numerator to decide how many equal-sized groups are selected. - Compare each multiplier with \(1\) and compare the selected region with the original amount.

Solution

1. In model a), \(20\) is split into \(5\) equal groups of \(4\), and \(4\) groups are selected. Thus \(\frac{4}{5}\times20=16\). 2. In model b), \(20\) is split into \(4\) equal groups of \(5\), and the model extends to a fifth group. Thus \(\frac{5}{4}\times20=25\). 3. The first multiplier is less than \(1\), so it shrinks the amount. The second is greater than \(1\), so it enlarges the amount.

Answer

\(\frac{4}{5}\times20=16\), which is less than \(20\). \(\frac{5}{4}\times20=25\), which is greater than \(20\).
Fraction × whole number interpretation 31
A \(14\)-foot section of trail is being resurfaced. Workers finish \(\frac{5}{6}\) of it. Use the model to explain the product and find how many feet are finished.
Figure for problem 541029

Hints

- The denominator tells how many equal parts the full length should be divided into. - The equal parts do not need to have whole-number lengths. - After finding one part, use the numerator to determine how many parts are included.

Solution

1. Partition \(14\) feet into \(6\) equal lengths: \(14\div6=\frac{14}{6}=\frac{7}{3}\) feet per part. 2. Take \(5\) parts: \(5\times\frac{7}{3}=\frac{35}{3}=11\frac{2}{3}\). 3. Therefore \(\frac{5}{6}\times14=11\frac{2}{3}\) feet.

Answer

Workers finish \(11\frac{2}{3}\) feet of trail.
Fraction × whole number interpretation 32
Priya finds \(\frac{2}{9}\times45\) by calculating \(45\div9=5\), then stops and says the answer is \(5\). Explain what Priya did correctly, what step is missing, and find the product.
Figure for problem 541056

Hints

- Count the equal rows in the model and connect them to ninths. - Decide what one row represents. - Then use the numerator to decide how many rows are needed.

Solution

1. Dividing \(45\) by \(9\) correctly finds one ninth of the collection: \(5\). 2. The numerator \(2\) means two of those one-ninth groups are needed. 3. Multiply \(2\times5=10\). 4. Therefore \(\frac{2}{9}\times45=10\).

Answer

Priya correctly found one ninth but forgot to take two such groups. The product is \(10\).
Fraction × whole number interpretation 33
A \(22\)-foot length is scaled to \(\frac{4}{9}\) of its original length. Explain \(\frac{4}{9}\times22\) by first finding one ninth of \(22\), then taking \(4\) such parts. What is the scaled length?

Hints

- The denominator tells how many equal parts the original length is divided into. - One equal part does not have to be a whole-number length. - Use the numerator to combine the needed number of equal parts.

Solution

1. One ninth of \(22\) feet is \(22\div9=\frac{22}{9}\) feet. 2. Four such parts give \(4\times\frac{22}{9}=\frac{88}{9}\) feet. 3. Convert \(\frac{88}{9}=9\frac{7}{9}\) feet.

Answer

The scaled length is \(9\frac{7}{9}\) feet.
Fraction × whole number interpretation 34
Use the model to represent selecting \(5\) of its equal groups. Write a fraction multiplication expression for the selected objects and find how many objects are selected.
Figure for problem 541112

Hints

- The number of equal groups created from the whole becomes the denominator. - The number of groups selected becomes the numerator. - Use the group size to find the selected number of objects.

Solution

1. Dividing the whole collection into \(8\) equal groups means the denominator is \(8\). 2. Selecting \(5\) groups means the numerator is \(5\), so the expression is \(\frac{5}{8}\times32\). 3. Each group contains \(32\div8=4\) objects. 4. Five groups contain \(5\times4=20\) objects.

Answer

The expression is \(\frac{5}{8}\times32\), and \(20\) objects are selected.
Fraction × whole number interpretation 35
Each whole bar represents \(12\) feet. Which model, a) or b), correctly represents \(\frac{5}{3}\times12\)? Explain why the other model uses the wrong-sized parts, then find the product.
Figure for problem 554448

Hints

- The denominator of the multiplier tells how many equal parts each whole must have. - Check the partition size before counting colored parts. - After choosing the model, find the size of one fractional group of \(12\).

Solution

1. A multiplier of \(\frac{5}{3}\) requires thirds, so model a), where each whole is divided into \(3\) equal parts and \(5\) such parts are colored, is correct. 2. Model b) divides each whole into fourths, so its five colored parts represent \(\frac{5}{4}\), not \(\frac{5}{3}\). 3. One third of \(12\) feet is \(4\) feet, and five such groups make \(20\) feet. 4. Therefore \(\frac{5}{3}\times12=20\).

Answer

Model a) is correct. Model b) uses fourths instead of thirds. The product is \(20\) feet.
Fraction × whole number interpretation 36
The expression \(\frac{3}{b}\times24\) equals \(9\). The fraction is interpreted by dividing the \(24\) objects into \(b\) equal groups and taking \(3\) groups. Find \(b\) and explain your reasoning.

Hints

- Work backward from the selected number of objects to find the size of one selected group. - Then determine how many equal groups of that size make the full collection. - The denominator records the total number of equal groups in the whole.

Solution

1. Taking \(3\) equal groups gives \(9\) objects, so each group must contain \(9\div3=3\) objects. 2. Dividing \(24\) objects into groups of \(3\) creates \(24\div3=8\) equal groups. 3. Therefore \(b=8\), and \(\frac{3}{8}\times24=9\).

Answer

\(b=8\).
Fraction × whole number interpretation 37
A whole-number amount \(q\) is divided into \(7\) equal groups. Taking \(5\) of those groups gives \(15\). This situation is represented by \(\frac{5}{7}\times q=15\). Find \(q\) and explain how the group interpretation leads to your answer.

Hints

- Work backward from the amount represented by the selected groups. - Find the size of one equal group before rebuilding all the groups in the whole. - Use the original fraction multiplication equation to check the result.

Solution

1. Five equal groups total \(15\), so one group contains \(15\div5=3\). 2. The whole amount has \(7\) such groups, so \(q=7\times3=21\). 3. Check: \(\frac{5}{7}\times21=15\).

Answer

\(q=21\).
Fraction × whole number interpretation 38
A vegetable plot covers \(18\,\text{yd}^2\), which is \(\frac{3}{4}\) of the area of a community garden. What is the total area of the garden? Reason from three equal fourths rather than guessing.

Hints

- Treat \(18\,\text{yd}^2\) as three equal fourths of the whole area. - Find the area of one fourth before rebuilding all four fourths. - Check the total by finding three fourths of it.

Solution

1. Three fourths of the garden area equal \(18\,\text{yd}^2\). 2. One fourth of the area is \(18\div3=6\,\text{yd}^2\). 3. Four fourths make the whole garden, so the total area is \(4\times6=24\,\text{yd}^2\). 4. Check: \(\frac{3}{4}\times24=18\).

Answer

The garden has a total area of \(24\,\text{yd}^2\).

All problems may be used, copied and printed free of charge for school and tutoring, including paid tutoring. Commercial adaptations as well as publication or redistribution on the internet are not permitted.