As given , leftmost or the First digit cannot be zero,
So, there are 9 choices for the first digit: 1,2,3,4,5,6,7,8,9 Excluding 0
And the second, third and fourth digits you are choosing from 10 digits: 0,1,2,3,4,5,6,7,8,9
Similarly, the fifth digit you will be choosing from 5 digits: 1,3,5,7,9 (because Numbers has to be odd)
= [tex]9\times10\times10\times10\times5[/tex] = 45000
Hence, 45000 five-digit odd numbers are possible.
