Question

how many 6-digit numbers can be created using the digits 2, 3, 5, 7, 8, and 9 without repeating any digits within that 6-digit number?

Answer 1

Answer: 720

Reason:

There are 6 choices for the first slot, then 5 choices for the next, and so on until we count down to 1.

Multiply out those values: 6*5*4*3*2*1 = 720

For more information, search out "factorials".