How many 5 digit numbers can be formed with the digits 0,1,2,3 and 4 when repetition of digits is allowed?

Explanation

Total given digits = 5
We have to place these 5 digits at unit, tens, 100th, 1000th and 10000th place.
We cannot take 'O' at 1000th place, so this place can be filled in 4 ways.
Repetition of digits is allowed.
`:.` Each place out of unit, 10th, 100th and 1000th can be filled in 5 ways.
Now form multiplication rule
Total numbers `= 4 xx 5 xx 5 xx 5 xx 5 = 2500`.