TOT 156 1987 Autumn J7 3 triangles (blue, green and red) , common P
Source:
April 19, 2020
Coloringcombinatoricscombinatorial geometry
Problem Statement
Three triangles (blue, green and red) have a common interior point . Prove that it is possible to choose one vertex from each triangle so that point is located inside the triangle formed by these selected vertices. (Imre Barani, Hungary)