Question 840559
Find the measure of the sum of the exterior angles of a regular polygon with 20 sides?
Ans: The measure of the sum of the exterior angles of a regular
polygon is ALWAYS 360.
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The measure of each interior angle of a regular polygon is 150 degrees find the number of sides of the polygon?
Ans: Each interior angle has a corresponding exterior angle of 180-150 = 30 
degrees.
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Since the sum of the exterior angles is 360 there are 360/30 = 12 sides.
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Cheers,
Stan H.