Complete the table for a scale of \(1:200\). Pay attention to the units.
<table>
<tr>
<td><strong>Plan (cm)</strong></td>
<td>\(3\,\text{cm}\)</td>
<td></td>
<td>\(10\,\text{cm}\)</td>
<td></td>
<td>\(25\,\text{cm}\)</td>
</tr>
<tr>
<td><strong>Actual length (m)</strong></td>
<td></td>
<td>\(12\,\text{m}\)</td>
<td></td>
<td>\(50\,\text{m}\)</td>
<td></td>
</tr>
</table>
Hints
- First determine how many actual meters correspond to \(1\,\text{cm}\) on the plan.
- Multiply when moving from a plan length to an actual length.
- Divide when moving from an actual length to a plan length.
- Keep track of whether each value is in centimeters or meters.
Solution
1. A scale of \(1:200\) means \(1\,\text{cm}\) on the plan represents \(200\,\text{cm}\), or \(2\,\text{m}\), in the actual object.
2. Multiply plan lengths by \(2\,\text{m}\) per centimeter: \(3 \cdot 2\,\text{m} = 6\,\text{m}\), \(10 \cdot 2\,\text{m} = 20\,\text{m}\), and \(25 \cdot 2\,\text{m} = 50\,\text{m}\).
3. Divide actual lengths by \(2\,\text{m}\) per centimeter: \(12\,\text{m} \div 2\,\text{m} = 6\), so the plan length is \(6\,\text{cm}\); \(50\,\text{m} \div 2\,\text{m} = 25\), so the plan length is \(25\,\text{cm}\).
Answer
The missing values from left to right are \(6\,\text{m}\), \(6\,\text{cm}\), \(20\,\text{m}\), \(25\,\text{cm}\), and \(50\,\text{m}\).