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UKMT Junior Mathematical Challenge, 2023

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

Four congruent rectangles are arranged as shown to form an inner square of area $20\text{ cm}^2$ and an outer square of area $64\text{ cm}^2$ . What is the perimeter of one of the four congruent rectangles?

(A) $6\text{ cm}$ (B) $8\text{ cm}$ (C) $9.75\text{ cm}$ (D) $16\text{ cm}$ (E) $20\text{ cm}$

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