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Weekly Problem 36 - 2011

Challenge Level: Challenge Level:1

Ans: ½

Let the radius of the circle be r. This implies that the radius of the semicircle is 2r. The area of the semi circle is $1/2 \times \pi \times(2r)^2$, which is twice the area of the small circle.

This problem is taken from the UKMT Mathematical Challenges.

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