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Relatives of a number

Source: Mexican Mathematical Olympiad 2006 Problem 1

September 28, 2014
number theory proposednumber theory

Problem Statement

Let abab be a two digit number. A positive integer nn is a relative of abab if:
[*] The units digit of nn is bb. [*] The remaining digits of nn are nonzero and add up to aa. Find all two digit numbers which divide all of their relatives.