How Many Ways Can They Be Seated?

Eight people attend a meeting, sitting around a circular table. The four officers must sit in a row (next to one another), and the four other people may sit anywhere. How many ways can the eight people be seated?

Note: Two arrangements are considered distinct even if one is a rotation of the other.


The answer is 4608.

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2 solutions

Jesse Li
Oct 7, 2018

We can designate 4 seats for the officers, because they must sit next to each other. The number of ways they can be seated in the 4 seats is 4! or 24 .

The 4 other people may sit in 4! or 24 ways in the 4 other seats.

Each order they can be seated in has 8 rotations.

We can multiply the three numbers we have gotten. 24 × 24 × 8 24 \times 24 \times 8 = 4608 \boxed{4608}

Michael Mendrin
Oct 12, 2018

Why can't the officers sit next to each other in pairs? The problem doesn't say that all four have to sit together in a row.

I just changed the wording of the problem

Jesse Li - 2 years, 8 months ago

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