Maths Olympiad Prep

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UKMT Pink Kangaroo, 2023

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

A square of side-length 30 cm30\text{ cm} is divided into nine smaller identical squares. The large square contains three circles with radii 5 cm5\text{ cm} (bottom right), 4 cm4\text{ cm} (top left) and 3 cm3\text{ cm} (top right), as shown. What is the total area of the shaded part?

(A) 400 cm2400\text{ cm}^2 (B) 500 cm2500\text{ cm}^2 (C) (400+50π) cm2(400+50\pi)\text{ cm}^2 (D) (500−25π) cm2(500-25\pi)\text{ cm}^2 (E) (500+25π) cm2(500+25\pi)\text{ cm}^2

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