areas by lines in regular 12-gon (2020 Novosibirsk Oral Geo Oly 7.1)
Source:
April 27, 2021
geometrydodecagonarea
Problem Statement
All twelve points on the circle are at equal distances. The only marked point inside is the center of the circle. Determine which part of the whole circle in the picture is filled in.
https://cdn.artofproblemsolving.com/attachments/9/0/9a6af9cef6a4bb03fb4d3eef715f3fd77c74b3.png