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UKMT Junior Kangaroo, 2016

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The diameter of the circle shown is 10 cm. The circle passes through the vertices of a large rectangle which is divided into 16 identical smaller rectangles. What is the perimeter of the shape drawn with a dark line?

(A) $10$ cm (B) $16$ cm (C) $20$ cm (D) $24$ cm (E) $30$ cm

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