Q20 of 35 Page 3

Determine the number of sides of a polygon whose exterior and interior angles are in the ratio 1 : 5.

The sum of interior angles of a polygon = (n – 2) × 180° ……..(i)


The Sum of exterior angle of a plygon is 360°


According to the question:




On cross multiplication we get




(n - 2) = 10


n = 12


Therefore the numbers of sides in the polygon are 12.

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