Combination & permutation help!

39 Views Asked by Bumbble Comm At 12 Apr 2026 - 4:45

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I was thinking: 120 - 5C4 but the answer is 24.

Is anyone able to explain this for me?

There are 3 best solutions below

Bumbble Comm On 08 Jul 2014 - 4:58 BEST ANSWER

With 1 seat occupied, there are 4 left. There are 4! = 24 ways to position the remaining persons.

Bumbble Comm On 08 Jul 2014 - 4:56

Martha is sitting in the middle seat (seat number $3$). The other $4$ friends can sit on any of the seats $1,2,4,5$.

Bumbble Comm On 08 Jul 2014 - 4:59

Since there are 5 seats, Martha ends up in a particular seat one fifth of the time. One fifth of 120 is 24.