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Weekly Problem 19 - 2006

Stage: 3 Challenge Level: Challenge Level:2 Challenge Level:2

Three semicircles showing the rectangle and parts of a circle
The shaded area may be divided into a $ 2 \times 1$ rectangle plus a semicircle plus two quarter circles (all of radius $1$). Hence the total area is that of the rectangle plus a circle of radius $1$. Making $2 + \pi$

This problem is taken from the UKMT Mathematical Challenges.

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