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UKMT Senior Mathematical Challenge, 2025

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The diagram shows three circles with radii 1, 2 and 3. What is the ratio of the shaded area to the area of the largest circle?

(A) $1:3$ (B) $1:2$ (C) $\sqrt{2}:\sqrt{3}$ (D) $2:3$ (E) $4:9$

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