CEMC Cayley, 2009

Geometry Difficulty 2.0 Junior Find the answer Canada

In the diagram, the centre of the circle is $O$ . The area of the shaded region is 20% of the area of the circle. The value of $x$ is

(A) $18$ (B) $45$ (C) $60$ (D) $72$ (E) $90$

Figure for this problem

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