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Palindromes Are Special

Posted: August 18, 2025

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A numerical palindrome is a number that reads the same forward and backward. For example, 77, 121, 4664, or 54345. You are given a set of numbers that contains all three-digit positive integers that are palindromes. What is the probability that any thee-digit palindrome in this set is a multiple of eleven? In other words, what is the probability that any thee-digit palindrome is a multiple of eleven? The answer might surprise you.

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