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Algebra Difficulty 3.9 AMC 10/12 Find the answer South Africa

A palindromic number is a number that reads the same backwards as it does forwards.
For example: 1575115751 and 909909.

a) What is the smallest palindromic number greater than 20162016?

b) What is the largest palindromic number less than 20162016?

A number or a short expression. Spacing and $ signs are ignored.

Solution

a) 21122112, since the next smaller palindrome is 20022002, which is less than 20162016.

b) 20022002, since 21122112 is the next palindrome.

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