MathDB
inequalities in areas by chords of a non convex polygon

Source: TOT 419 1994 Spring A S7 - Tournament of Towns

June 12, 2024
inequalitiesgeometry

Problem Statement

Consider an arbitrary “figure” FF (non convex polygon). A chord of FF is defined to be a segment which lies entirely within F F and whose ends are on its boundary.
(a) Does there always exist a chord of FF that divides its area in half? (b) Prove that for any FF there exists a chord such that the area of each of the two parts of FF is not less than 1/3 1/3 of the area of FF. (c) Can the number 1/31/3 in (b) be changed to a greater one?
(V Proizvolov)