The digits 5, 7, 1, and 9 are to be used in a roll number in a school. How
many different roll numbers are possible if repetitions are not permitted?

Respuesta :

Answer:

1, 7, 5, 9
7, 1, 9, 5

9, 5, 1, 7

But there are about 10 possible combinations.

Step-by-step explanation:

Q&A Education