UKMT Pink Kangaroo, 2022

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The centres of the seven circles shown all lie on the same line. The four smaller circles have radius $1$ cm. The circles touch, as shown. What is the total area of the shaded regions?

(A) $\pi$ cm $^2$ (B) $2\pi$ cm $^2$ (C) $3\pi$ cm $^2$ (D) $4\pi$ cm $^2$ (E) $5\pi$ cm $^2$

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