Combinatorics

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Combinatorics

by levocap » Sat Aug 29, 2009 3:49 pm
Combinatorics as appeared on MGMAT

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Medals are to be awarded to three teams in a 10-team competition. If one medal is gold, one medal is silver, and one medal is bronze, how many different ways are there to award the three medals to teams in the competition?

10!/7! is the answer, which means that this is a permuation and not combination. But why?
The order of who receives Gold, Silver, Bronze does not matter so I would think it is combination no?
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Re: Combinatorics

by pathaniaus » Sat Aug 29, 2009 5:55 pm
levocap wrote:Combinatorics as appeared on MGMAT

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Medals are to be awarded to three teams in a 10-team competition. If one medal is gold, one medal is silver, and one medal is bronze, how many different ways are there to award the three medals to teams in the competition?

10!/7! is the answer, which means that this is a permuation and not combination. But why?
The order of who receives Gold, Silver, Bronze does not matter so I would think it is combination no?
Yeah man I understand what you're saying. But think of it this way, the items awarded are DIFFERENT. They are not all getting the SAME prize. If all three were to receive gold, then the order of the would not matter, and thus a combination. but they are awarded different items and therefore order DOES matter

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