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The diagram shows a regular dodecagon (a polygon with twelve equal sides and equal angles).
What is the size of the marked angle?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
Dodecagon Angles
Age 11 to 14
ShortChallenge Level 
The diagram shows a regular dodecagon (a polygon with twelve equal sides and equal angles).
What is the size of the marked angle?
If you liked this problem, here is an NRICH task which 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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