UKMT Pink Kangaroo, 2023

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

A large square of side-length $10\text{ cm}$ contains a smaller square of side-length $4\text{ cm}$ , as shown in the diagram. The corresponding sides of the two squares are parallel. What percentage of the area of the large square is shaded?

(A) $25\%$ (B) $30\%$ (C) $40\%$ (D) $42\%$ (E) $45\%$

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