Problem Solving

Hi LUANDATO,

We're told that 5 people are to be seated around a circular table and that two sitting arrangements are considered different only when the positions of the people are different relative to each other. We're asked for the total number of possible sitting arrangements of the group.

If the 5 people were sitting in a straight-line, then we'd be dealing with a standard Permutation question - and there would be 5! = 120 possible arrangements. Here, we're dealing with a circular table, so any of the 5 chairs could be the "first chair" and 1 arrangement of people could be created in 5 different ways. Thus, we have to divide 120 by 5 to determine the number of unique arrangements. 120/5 = 24 arrangements.

Final Answer: C

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LUANDATO wrote:At a dinner party 5 people are to be seated around a circular table. Two sitting arrangements are considered different only when the positions of the people are different relative to each other. What is the total number of possible sitting arrangements or the group?

A. 5
B. 10
C. 24
D. 32
E. 120

When determining the number way to arrange a group around a circle we subtract one from the total and set it to a factorial. Thus, the total number of possible sitting arrangements for 5 people around a circular table is 4! = 24.

Answer: C