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Algebra Difficulty 1.2 Junior Find the answer Canada

A rectangle has length 13 and width 10. The length and the width of the rectangle are each increased by 2. By how much does the area of the rectangle increase?

Pick one

Solution

The area of the original rectangle is $13 \times 10 = 130$ .

When the dimensions of the original rectangle are each increased by 2, we obtain a rectangle that is 15 by 12.

The area of the new rectangle is $15 \times 12 = 180$ , and so the area increased by $180 - 130 = 50$ .

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.