Question

For a convex 19-gon, what is the sum of the measures of the interior angles?

Answer 1

The measure of the sum of the interior angles of a convex n-gon is (n − 2)π radians, or (n − 2)*180 degrees. 

The particular solution here is (19 − 2)π, or 19π radians, which is 19*180, or 3420 degrees.