Each interior angle of a regular polygon is 120 greater than each exterior angle calculate the number of sides

Step-by-step explanation:

Let exterior angle be x

Interior angle =  x + 120

Interior angle and exterior angle are linear pair

x +x +120 = 180

2x + 120 = 180

         2x = 180 - 120

         2x = 60

           x = 60/2

x = 30°

No. of sides = 360°/measurement of exterior angle

                    = 360/30

                     = 12 sides