Question

@phi

Answer 1

There are 10 teams in the Eastern Division of the Ontario Hockey league.

How many ways can the season end if we know that Niagara, Sudbury, and Mississauga will be together in the standings?

Answer 2

I just don't get permutations and combinations. Can you please help me on them???

Answer 3

put those 3 into 1 "bag"
now you have 7 teams + 1 bag
how many ways can you order 8 things?
hint: it's a permutation

Answer 4

So we would have \(8! \times 3!\) right?

Answer 5

yes, the 8! give you all the ways you order the 8 objects
but once we do that, we can order the 3 teams grouped together and that gives another factor of 3!

Answer 6

Thank you. Can you give me tips on how to approach problems like these? I just sometimes can't identify which one is a permutation vs. combination. Please don't just say that one of them has order that matters and the other doesn't have order. I need more explanation than that. I have a quiz on that tomorrow and I am lost :(

Answer 7

It's confusing until you do a bunch of problems.
I would do lots of problems. Then when you do the test, try to match up the question to one of the problems you already did.

Answer 8

Are there any certain keywords I should watch out for?

Answer 9

more like "type of problems"
for example, "number of committees of 3 people out of 10 to choose"
that is combination (if you choose A, B and C, it does not matter which you choose first)
try these problems
http://www.mathwarehouse.com/probability/combination.php

Answer 10

okay thank you!

Answer 11

in each of those problems the answer is some large number CHOOSE smaller number
if you can match a problem with one of these, then you know the answer
(the math to figure out what 10C3 works out to, is not too hard to learn)