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The large equilateral triangle is fixed in position. Two of the small equilateral triangles are to be painted black and the other two are to be painted white. In how many ways can this be done?
If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.
Half and Half
Age 11 to 14
ShortChallenge Level 
The large equilateral triangle is fixed in position. Two of the small equilateral triangles are to be painted black and the other two are to be painted white. In how many ways can this be done?If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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