Question

a lock has a code of 5 numbers between 1 and 20 . If no numbers in the code are allowed to repeat, how many different codes could be made?


Thank you

Answer 1

20C5

Answer 2

20 * 19 * 18 * 17 * 16

Answer 3

oobleck is correct

its a code ... so the same numbers can be used in a different order

Answer 4

so ....15,504?

Answer 5

what do i do with these?
20 * 19 * 18 * 17 * 16