At a dinner party

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At a dinner party

by sanju09 » Mon Mar 12, 2012 2:25 am
At a dinner party, 5 people are to be seated around a circular table. Two seating arrangements are considered different only when the positions of the people are different relative to each other. What is the total number of different possible seating arrangements for the group?
(A) 5
(B) 10
(C) 24
(D) 32
(E) 120
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by killer1387 » Mon Mar 12, 2012 2:40 am
4! i.e. 24
Hence C

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by Anurag@Gurome » Mon Mar 12, 2012 6:11 am
sanju09 wrote:At a dinner party, 5 people are to be seated around a circular table. Two seating arrangements are considered different only when the positions of the people are different relative to each other. What is the total number of different possible seating arrangements for the group?
(A) 5
(B) 10
(C) 24
(D) 32
(E) 120
For circular seating arrangement, the number of arrangements of n distinct objects in a row is given by n!.
Number of arrangements of n distinct objects in a circle is given by (n - 1)!.

So, in this the total number of different possible seating arrangements for the group = (5 - 1)! = 4! = 4 * 3 * 2 * 1 = 24 ways

The correct answer is C.
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by Neo Anderson » Mon Mar 12, 2012 8:55 am
(5-1)! = 24