I am a polygon whose interior angles sum up to the exact same value as my exterior angles. How many sides do I have?
4 sides
The sum of interior angles of an n-sided polygon is (n-2)*180. The sum of exterior angles of any convex polygon is always 360 degrees. Setting (n-2)*180 = 360 gives n-2 = 2, so n = 4 (a quadrilateral).
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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