Comparing the measure of an internal angle to the measure of an external angle of a regular polygon is 5:1. Find the number of sides of the polygon.
Show answer & explanation
Correct answer: C
Explanation
Let the exterior angle = x°
Interior : Exterior = 5 : 1
Interior angle = 5x°
Interior angle + Exterior angle = 180°
5x + x = 180°
6x = 180°
x = 30°
Therefore, each exterior angle = 30°
In a regular polygon,
Number of sides = 360° / Exterior angle
= 360 / 30= 12