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Overlapping Beer Mats

Age 11 to 14 Short
Challenge Level

Two beer mats, each the shape of a regular hexagon with area 36cm$^2$, are placed on top of each other, as shown below.


If they are placed so that the corner of the lower beer mat is in the centre of the higher beer mat, as shown below, what is the area of the overlap?

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

This problem is adapted from the World Mathematics Championships

You can find more short problems, arranged by curriculum topic, in our short problems collection.