MathDB
TOT 2006 Fall - Senior O-Level p1 sum of numbers in Mary's notebook

Source:

February 25, 2020
number theory

Problem Statement

Three positive integers xx and yy are written on the blackboard. Mary records in her notebook the product of any two of them and reduces the third number on the blackboard by 11. With the new trio of numbers, she repeats the process, and continues until one of the numbers on the blackboard becomes zero. What will be the sum of the numbers in Mary's notebook at that point? (4)