Junior Regional Olympiad - FBH 2016 Grade 7 Problem 5
Source:
September 29, 2018
tablecombinatorics
Problem Statement
In table
https://services.artofproblemsolving.com/download.php?id=YXR0YWNobWVudHMvZC9hLzBjNjFlZWFjM2ZlOTQzMTk2YTdkMzQ2MjJiYzYyMWFlN2Y0ZGZlLnBuZw==&rn=dGFibGljYWEucG5n numbers are circled, in every row and every column exactly one. Prove that among them, there are at least two equal