Regional Olympiad - Republic of Srpska 2004 Grade 9 Problem 4
Source: Regional Olympiad - Republic of Srpska 2004
September 19, 2018
SetscombinatoricsDivisiondisjointSubset
Problem Statement
Set is firstly divided on disjoint nonempty subsets, and then on disjoint nonempty subsets. Prove that some elements of set were after first division in same set, and after the second division were in different sets