Two similar shapes have corresponding lengths of cm and cm. The smaller shape has area cm. What is the area of the larger shape?
Answer and explanation
Correct answer: A. 75 cm
- Step 1: Length scale factor: .
- Step 2: Area scale factor: .
- Step 3: Area: cm.
Answer
75 cm.
Why not the others: 30 cm: This multiplies the area by the length scale factor only. 187.5 cm: This uses the cube of the scale factor, which applies to volume. 16.5 cm: This adds the difference in lengths to the area.
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