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## 'Weekly Problem 52 - 2012' printed from http://nrich.maths.org/

The diagram shows an irregular hexagon with interior angles all equal to 120 degrees made by cutting the corners off a piece of card in the shape of an equilateral triangle with sides of length 20 units.

An identical hexagon could also be made by cutting the corners off a different equilateral triangle.

What is the side length of this triangle?

If you liked this problem,

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*This problem is taken from the UKMT Mathematical Challenges.*

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