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101 brown points, 101 green points, equal sums of 1-coloured segments

Source: Ukrainian Geometry Olympiad 2020, X p5 , XI p4

April 27, 2020
Coloringcombinatoricscombinatorial geometrygeometrypoints

Problem Statement

On the plane painted 101101 points in brown and another 101101 points in green so that there are no three lying on one line. It turns out that the sum of the lengths of all 50505050 segments with brown ends equals the length of all 50505050 segments with green ends equal to 11, and the sum of the lengths of all 1020110201 segments with multicolored equals 400400. Prove that it is possible to draw a straight line so that all brown points are on one side relative to it and all green points are on the other.