There are 900 6-digit palindromes.
35.
-1000
900 This explains it. A positive integer is a palindrome if it reads the same forward and backwards such as 1287821 and 4554. Determine the number of 5-digit positive integers which are NOT palindromes. We start by counting the total number of 5 digit positive integers. The first digit is between 1 and 9, so we have 9 choices. Each of the other 4 digits can be anything at all (10 choices for each). This gives us 9(10)4 = 90000 five-digit positive integers. Now we need to count the number of 5 digit palindromes. Again, we have 9 choices for the first digit and 10 choices for each of the next two. The tens and units digits however are fixed by our choices so far. Therefore, there are only 900 five-digit palindromes. Therefore, the total number of five-digit positive integers which are not palindromes is 90000-900 = 89100.
1-digit: 9 2-digit: 9 3-digit: 9 x 10 = 90 4-digit: 9 x 10 = 90 5-digit: 9 x 10 x 10 = 900 6-digit: 9 x 10 x 10 = 900
Five of them.
There are 90 four-digit palindromes
There is 90 four digit palindromes.
There are 90 four-digit palindromes
There are no four-digit perfect squares that are palindromes.
There are 900 6-digit palindromes.
There are 10 3-digit odd palindromes that are divisible by five.
9 of them.
90 of them.
90
For there to be palindromes, each digit must be replicated. Therefore there are at most three distinct digits.If there are 3 pairs of different digits, then there are 6 palindromes. If there can be more duplicate digits, then there are 27 palindromes.
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