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100 discs on the plane so that each two of them have a common point ...

Source: Sharygin Geometry Olympiad 2015 Final 9.3

August 1, 2018
geometrycombinatorial geometrycircles

Problem Statement

Let 100100 discs lie on the plane in such a way that each two of them have a common point. Prove that there exists a point lying inside at least 1515 of these discs.
(M. Kharitonov, A. Polyansky)