Question

The size of each interior angle of a regular polygon is five times the size of the exterior angle. Find the number of sides of the polygon.

Answer 1

Exterior < = 360
                     n
Interior < = 180 - 360
                             n
180 – 360 = 5 ( ³⁶⁰/_n )             
           n
180n – 360 = 1800
            n          n              
180n = 2160
      n = 12