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#1 2007-08-09 13:48:35

tonyz1949
Member
Registered: 2007-08-04
Posts: 20

Permutation/Combination

How many different teams of 2 people each can Joshua select from a group of 5 people?

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#2 2007-08-09 16:09:43

pi man
Member
Registered: 2006-07-06
Posts: 251

Re: Permutation/Combination

That would be (5 choose 2).  The general formula for (X choose Y) is X! / (N! * (X-N)!).

(5 choose 2)= 5! / (2! * (5-2)!) = 5! / (2! * 3!) = 5*4*3*2*1 / (2*1 * 3*2*1) = 10

If order was important (the team of Jane and Joe would be considered different  from the team of Joe and Jane), then then answer would be 5 * 4 = 20.

Last edited by pi man (2007-08-09 16:11:46)

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#3 2007-08-10 01:10:14

tonyz1949
Member
Registered: 2007-08-04
Posts: 20

Re: Permutation/Combination

Thank You piMan;)

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