How many different 3-digit numbers can you make with the following digits if no digit may be repeated in the same number?

Question

2 7 8 0 3 1

Is there any way I can solve this problem by writing equation?

Answer 1

there are 5 choices for the 1st (leftmost) digit
... a "leading" zero is not standard form

5 choices for the 2nd digit
... zero is available

4 choices for the 3rd digit

5 * 5 * 4 = ?

Answer 2

Answer is 6*5*4=120
Thank you anyway!