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Right Angles
Age 11 to 14
Challenge Level 
The problem Triangles in Circles will help if you are having difficulty calculating angles.
Try an even number of points round the edge.
Proving this will be easier if you join all the points to the centre and look for isosceles triangles.
Try an even number of points round the edge.
Proving this will be easier if you join all the points to the centre and look for isosceles triangles.
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