Which of the following best describes a regular polygon when the sum of its interior angles is 1260?

a- pentagon
b- hexagon
c- octagon
d- nonagon

Nonagon - 9 sides

Sum of interior angle of a polygon is (n-2)180 = x

N is the number of sides, so when you plug in 1260 for x, you get 9 for n

Hi!  So, in order to find the mean, we must add all the numbers together, then divide it by how many sets of numbers there are.  So, 39 + 43 + 46 + 86 + 22 + 39 + 75 = 350.  Now, there are 7 sets of numbers.  So, we do 350 / 7.  Which equals B) 50.  Hope this helps! :-)