Math Prize 2017 Problem 19
Source:
September 27, 2017
Math Prize for Girls
Problem Statement
Up to similarity, there is a unique nondegenerate convex equilateral 13-gon whose internal angles have measures that are multiples of 20 degrees. Find it. Give your answer by listing the degree measures of its 13 external angles in clockwise or counterclockwise order. Start your list with the biggest external angle. You don't need to write the degree symbol .