*palindrome*, such as $83438$, is a number that remains the same when its digits are reversed. How many four digit numbers are not palindromes?

## Dhaka Junior 2011/5

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### Dhaka Junior 2011/5

5. A

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**Posts:**78**Joined:**Thu Jan 20, 2011 10:46 am

### Re: Dhaka Junior 2011/5

Four digit palindrome number should be like ABBA.If u reverse it u will get also ABBA.At first we will count how many numbers are palindrome.It is enough to count AB.SO we will get the result 9o.Then the ans 10000-90=9910

### Re: Dhaka Junior 2011/5

I did not get it. 9*9=81 should be palindromic numbers

### Re: Dhaka Junior 2011/5

4 digit number starts from 1000 soMehfuj Zahir wrote:Four digit palindrome number should be like ABBA.If u reverse it u will get also ABBA.At first we will count how many numbers are palindrome.It is enough to count AB.SO we will get the result 9o.Then the ans 10000-90=9910

there are 9000 4 digit numbers therefore the answer should be 8910

© Shafin Ahmed

### Re: Dhaka Junior 2011/5

surjo wrote:I did not get it. 9*9=81 should be palindromic numbers

mate it will be 9 * 10