Question

Sonji bought a combination lock that opens with a four-digit number created using the digits 0 through 9. The same digit cannot be used more than once in the combination.

If Sonji wants the last digit to be a 7 and the order of the digits matters, how many ways can the remaining digits be chosen?

84
504
3,024
60,480

Answer 1

Answer:

504 combos

Step-by-step explanation:

Cannot use digits twice and last is '7'

 9 digits for first place choice  

     8 digits for second place

         7 digits for third place

               only  '7' for fourth place       9 x 8 x7 = 504 combos