error in multplication of 2 naturals (V Soros Olympiad 1998-99 Round 3 10.7)
Source:
May 26, 2024
number theory
Problem Statement
High school graduate Igor Petrov, who dreamed of becoming a diplomat, took the entrance exam in mathematics to Moscow University. Igor remembered all the problems offered during the exam, but forgot some numerical data in one. This is the task:“When multiplying two natural numbers, the difference of which is , an error was made: the hundreds digit in the product was increased by . When dividing the resulting (incorrect) product by the smaller of the factors, the result was quotient and remainder .. Find the numbers that needed to be multiplied.” .The values of and were given in the condition, but Igor forgot them. However, he remembered that the problem had two answers. What could the numbers and be equal to (they are both integers and positive)?Note. The problem in question was proposed at one of the humanities faculties of Moscow State University in 1991.