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UKMT Junior Kangaroo, 2025

Geometry Difficulty 1.0 Junior Find the answer United Kingdom

Joseph draws a square with side-length $10$ cm. He joins the midpoints of the sides to make a smaller square, as shown in the diagram. What is the area, in $\text{cm}^2$ , of the smaller square?

(A) $10$ (B) $20$ (C) $30$ (D) $40$ (E) $50$

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