SOLUTION: How many different committees of 5 people can be formed from a group of 12 volunteers? Is that a permutation or combination?

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Question 610992: How many different committees of 5 people can be formed from a group of 12 volunteers? Is that a permutation or combination?
Answer by ashipm01(26) About Me  (Show Source):
You can put this solution on YOUR website!
This would be a combination since the order each person is selected in does not matter. So the following subcommittees are all the same even though the ordering is different:
{1, 2, 3, 4, 5}, {5, 4, 3, 2, 1}, {2, 3, 5, 1, 4}
Since it does not matter the ordering of the people in the groups, it is a combination.
So now you can use the n choose r function:
ncr%28n%2C+r%29+=+%28n%21%29%2F%28r%21%2A%28n-r%29%21%29
Typically it is written as two numbers, one on top of the other, inside a pair of parenthesis, but I am not sure how to format it like that on this site so I called it ncr(n, r) which means "n choose r".
So substituting 12 for n and 5 for r in the above equation yields a value of 792 possible ways of choosing 5 people at a time from a set of 12 people.