2013 ToT Fall Junior A p1 0 red, 100 yellow and 100 green sticks
Source:
March 22, 2020
combinatoricsColoringcombinatorial geometry
Problem Statement
There are red, yellow and green sticks. One can construct a triangle using any three sticks all of different colours (one red, one yellow and one green). Prove that there is a colour such that one can construct a triangle using any three sticks of this colour.