Answer to Question #313668 in Statistics and Probability for Kayla

Question

How many different ID cards can be made if there are 9 digits on a card and no digit can be used more than once? What if digits can be repeated?

Answer 1

Without repetition: $N=10*9*8*7*6*5*4*3*2=3626800$ .

With repetition: $N=10^9=1000000000.$