MathDB

5

Part of 1977 Czech and Slovak Olympiad III A

Problems(1)

Colored collinear points

Source: Czech and Slovak Olympiad 1977, National Round, Problem 5

10/10/2024
Let A1,…,AnA_1,\ldots,A_n be different collinear points. Every point is dyed by one of four colors and every of these colors is used at least once. Show that there is a line segment where two colors are used exactly once and the other two are used at least once.
combinatorial geometryColoringpoints