Question

Caroline and 2 friends are going to the mall on a bus. In how many different orders can the girls get into the front of the bus?

Answer 1

The girls can get into the front of the bus in 6 different ways.
abc
acb
bac
bca
cab
cba

Answer 2

3!, or 1*2*3, or 6.  Thus is answered by the factorial function (!)