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UKMT Grey Kangaroo, 2025

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

Peter has drawn a rectangular flag with dimensions $12\text{cm}$ by $9\text{cm}$ . He has drawn a quarter-circle with centre at each corner and coloured the region formed, as shown. What is the length indicated by the question mark?

(A) $5\text{ cm}$ (B) $6\text{ cm}$ (C) $7\text{ cm}$ (D) $8\text{ cm}$ (E) $9\text{ cm}$

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