Engineering Board Exam Reviewer · Circular and Cyclic Permutations · medium

In how many ways can 6 people be seated around a round table if two particular people refuse to sit next to each other?

  1. 48
  2. 120
  3. 72
  4. 96

Answer

C. 72

Solution

Total arrangements: (6-1)!=120. Arrangements with the two together: treat them as one unit, giving (5-1)!=24 ways times 2 orders =48. So 120-48=72.

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