Question 86
A circle of length $6N$ is divided by $3N$ marked points into $3N$ arcs: $N$ arcs of length $1$, $N$ arcs of length $2$ and $N$ arcs of length $3$.
Prove that among the marked points there exist two which are endpoints of some diameter of the circle. (V. Prasolov, Problems in plane and solid geometry)
Prove that among the marked points there exist two which are endpoints of some diameter of the circle. (V. Prasolov, Problems in plane and solid geometry)