Question

there are 20 swimmers on the swim team. how many different groups of 5 can there be?

Answer 1

C(20,5) =

20! 20! 20*19*18*17*16
----------- = ----------- = ----------------
(20 - 5)! * 5! 15! * 5! 5!

Answer 2

what do the exclamation marks ! mean???

Answer 3

Those are factorial symbols. Your teacher HAD to have covered that if you all are doing problems like this. Have you heard of factorial?

Answer 4

no haha