$\begin{array}{1 1} 96 \\ 120 \\ 2500 \\ 2404 \end{array}$

If repetitions are allowed, the no. of 5 digit numbers =

$4\times 5\times 5\times 5\times 5=2500$

(since '0' cannot come in first place)

No. of 5 digit numbers in which no number is repeated=

$4\times 4\times 3\times 2\times 1=96$

$\Rightarrow\:No. of numbers in which at least one digit is repeated=

$2500-96=2404$

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