Question

How many different 5-digit numbers can you write using each of the digits 0, 1, 2, 3, 4 exactly once?

Answer 1

96

Explanation:

To get 5 digit numbers using the digits 0,1,2,3,4 exactly once = 4*4*3*2*1 = 96.

Step 1:

1st digit can be 1, 2,3,4 ( it can't be 0) so there are 4 choices.

Step 2:

2nd digit = 4 choices.

Step 3:

3rd digit = 3 choices

Step 4:

4th digit = 2 choices

Step 5:

5th digit = 1 choice .

So the number of different 5 digit number is 4*4*3*2*1 = 96