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Permutations

by Ferrari » Wed Dec 02, 2009 5:37 pm
Q. In how many ways 5 rings of different types can be worn in 4 fingers?

My answer is 5*5*5*5, because one finger can wear 5 ways, similarly other three fingers.
But this is not the correct answer.
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by papgust » Wed Dec 02, 2009 6:45 pm
IMO it should be 5*4*3*2 (If the question DOES'NT ask for repetition)

First finger has 5 rings to wear. After choosing a ring for first finger, you have four rings for the second finger. And so on.

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by Stuart@KaplanGMAT » Wed Dec 02, 2009 7:32 pm
Ferrari wrote:Q. In how many ways 5 rings of different types can be worn in 4 fingers?

My answer is 5*5*5*5, because one finger can wear 5 ways, similarly other three fingers.
But this is not the correct answer.
Is that the entire question?

Nowhere does it say there's a minimum or maximum number of rings per finger, so we can't assume that it's one on each.
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by Ferrari » Wed Dec 09, 2009 8:31 am
Thanks for your response.
Yes, that is all the question, there is no constraints on wearing rings.