Dhaka Junior 2011/5
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Please don't post problems (by starting a topic) in the "Junior: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
Please don't post problems (by starting a topic) in the "Junior: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
5. A palindrome, such as $83438$, is a number that remains the same when its digits are reversed. How many four digit numbers are not palindromes?
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Please install LaTeX fonts in your PC for better looking equations,
learn how to write equations, and don't forget to read Forum Guide and Rules.
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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