olymmath

RU-TST 2016

Russian IMO Team Selection Test 2016.

Other problems

Problem 4

A regular nn{} -gon and a regular mm -gon with distinct vertices are inscribed in the same circle. The vertices of these polygons divide the circle into n+mn+m arcs. Is it always possible to inscribe a regular (n+m)(n+m) -gon in the same circle so that exactly one of its vertices is on each of these arcs?