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UKMT Pink Kangaroo, 2024

Geometry Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

The figure shows a square with four circles of equal area, each touching two sides of the square and two other circles. What is the ratio between the area of the black region and the total area of the grey regions?

(A) $1:4$ (B) $1:3$ (C) $2:3$ (D) $3:4$ (E) $\pi:1$

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