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October 23, 2024
geometrycombinatoricsChile

Problem Statement

In a regular polygon with 100 vertices, 10 vertices are painted blue, and 10 other vertices are painted red.
1. Prove that there exist two distinct blue vertices A1 A_1 and A2 A_2 , and two distinct red vertices R1 R_1 and R2 R_2 , such that the distance between A1 A_1 and R1 R_1 is equal to the distance between A2 A_2 and R2 R_2 .
2. Prove that there exist two distinct blue vertices A1 A_1 and A2 A_2 , and two distinct red vertices R1 R_1 and R2 R_2 , such that the distance between A1 A_1 and A2 A_2 is equal to the distance between R1 R_1 and R2 R_2 .