Hi, I need someone to check my work and I have a question.

Question

Polygon: pentagon
Number of sides: 5
Smallest number of interior triangles: 3
Now, here's my question:
Sum of degrees of the interior angles:
___*180=_____ degrees

Answer 1

sum of degrees of exterior right turns = 360 (all the way around)
360/5 = 72
so each interior angle is 180 - 72 = 108
and
5*108 = 540