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3 years ago

How many 5-digit palindromes contain only even digits?

Mathematics

1 answer:

34kurt3 years ago

3 0

Answer:

The correct answer is - 900

Step-by-step explanation:

A palindrome is a positive integer that is same whether read from left to right or from right to left. For example, 123321 palindromes.

An n-digit palindrome is determined from the first n/2 digits if n is even, and from the first n+1/2 digits if n is odd.

Therefore, if n is even, there are 9×10⁽n⁻²/²⁾ palindromes; and if n is odd, there are 9×10⁽n₋²/²⁾ palindromes. where n is number of digits.

For n=5 , there are 9×10²=900 palindromes

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