Question

You are creating your highschool schedule and you get to pick what times you take each class. You have Geometry, Earth Science, English Literature, Ancient History and Music Appreciation. You have 7 class periods to choose from. How many different ways can you arrange your schedule? Help with this please?

Answer 1

Each subject can be assigned to a "class period"
For Geometry, we pick any of the 7 available.
that leaves 6 for the next subject, then 5, and so on.
we have
7*6*5*4*3
ways to make the assignments.

Answer 2

order matters so this is a permutation.
repetition is not allowed (once we assign a class period, we can't re-use it)
see
http://www.mathsisfun.com/combinatorics/combinations-permutations.html
for a short explanation... under permutations without repetition

Answer 3

So I multiply 7*6*5*4*3, do I not include 2?
Thank you for your help!

Answer 4

we use 5 numbers because we have 5 subjects.

Answer 5

if we had just 1 subject, and 7 class periods
we have 7 choices for what period we assign

if we had 2 subjects, we could assign 1 of the 7 periods to the first subject, and 6 to the 2nd subject. We would have 7*6 = 35 ways to make those assignments.
(If you get bored, and want to fill your time, try finding all 35 ways)