MathDB
Game on 3X3 table

Source: 12th Dürer Math Competition ,First Round, Category E , P3

August 18, 2020
tablecombinatorics

Problem Statement

a) We are playing the following game on this table: In each move we select a row or a column of the table, reduce two neighboring numbers in that row or column by 11 and increase the third one by 11. After some of these moves can we get to a table with all the same entries?
b) This time we have the choice to arrange the integers from 11 to 99 in the3×3 3 \times3 table. Still using the same moves now our aim is to create a table with all the same entries, maximising the value of the entries. What is the highest possible number we can achieve?