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Weekly Problem 52 - 2014
Four arcs are drawn in a circle to create a shaded area. What fraction of the area of the circle is shaded?
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Problem

Image
In or Out?


The shaded region shown in the diagram is bounded by four arcs, each of the same radius as that of the surrounding circle.


What fraction of the surrounding circle is shaded?


 


If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.