CEMC Pascal, 2025

Geometry Difficulty 2.4 Junior Find the answer Canada

A small square is drawn inside a larger square, as shown.

The area of the shaded region and the area of the unshaded region are
each $\text{18 cm 2}$ . What is the
side length of the larger square?

Pick one

Solution

The area of the shaded region and the area of the unshaded region
are each equal to $18 \text{ cm}^2$ .
The area of the larger square is equal to the sum of the areas of the
shaded and unshaded regions, which is $18 \text{ cm}^2+18 \text{ cm}^2=36 \text{ cm}^2$ .

Thus, the side length of the larger square is $\sqrt{36 \text{ cm}^2}=6 \text{ cm}$ .

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