A figure with area 1 is cut out of paper. We divide this figure into 10 parts and color them in 10 different colors. Now, we turn around the piece of paper, divide the same figure on the other side of the paper in 10 parts again (in some different way). Show that we can color these new parts in the same 10 colors again (hereby, different parts should have different colors) such that the sum of the areas of all parts of the figure colored with the same color on both sides is ≥101. geometrycombinatoricsareacombinatorial geometrydissectionIMO ShortlistIMO Longlist