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UKMT Senior Mathematical Challenge, 2018

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

A semicircle is inscribed in a quarter circle as shown. What fraction of the quarter circle is shaded?

(A) $\frac{1}{3}$ (B) $\frac{1}{\sqrt{3}}$ (C) $\frac{2}{3}$ (D) $\frac{\sqrt{3}}{2}$ (E) $\frac{1}{\sqrt{2}}$

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