EAMCET Engineering 2005 Solved Paper

If the last two digits is 0,0 , then in Ist digit any of the numbers except 0
i.e., 9 numbers
If the last two digits is 1,1 , then in Ist digit any of the numbers except 0 and 1 , i.e. 8 numbers
∴ The total number of numbers
=9+8×9=81