Pushed together

A square containing two semicircles. The red line segment is a common tangent. What fraction is green?

Scroll down for a solution to this problem.


The green fraction is 1/8.

Solution by Matthew Arcus.

Drawing in some parallels and filling in the angles shows green area is that of half a square with side the circle radius, so 1/8 the area of the main square.


Please find here the video solution: Video: Pushed together.

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