The number of 5-digits numbers that can be formed using the digits 0, 1, 1, 2, 3 is
If repetitions are allowed, the no. of 5 digit numbers
⇒4×5×5×5×5
4×5×5×5×5=2500
(since '0' cannot come in first place)
=2500
No. of 5 digit numbers in which no number is repeated
⇒4×4!2!
(since '1' occurs twice)
=48