Answer: 170
Explanation:
Let L be the sum of the degree measures of the 10 larger interior angles, and S be the sum of the degree measures of the 10 smaller interior angles. The angles in a convex 20-sided polygon add up to 180(20-2)=3240 degrees, which tells us that L+S=3240. The problem also tells us that L-S=160. Adding both equations together, we get $2L=3400, and by dividing by 2, we get L=1700. Therefore, the sum of the 10 larger interior angles is 1700 degrees, and the average measure of these angles is 1700/10
=170