Question

Allie remembered that the 3 digits in her locker combination were 2, 4, and 8, but she forgot the order of the numbers what is the maximum number of combinations she must check in order to open her lock?

Answer 1

You need to calculate all possible permutations of 3 elements/numbers (without repetition) which is given by n!
3!=3*2*1=6 possible permutations/lock combinations she has to check at most.