CA Foundation · Quantitative Aptitude · Seating Arrangements
In how many different ways can 5 persons be seated around a circular table if only the relative positions of the persons matter (rotations count as the same arrangement)?
The answer is 24. In a circular arrangement, rotations of the same seating are identical, so one person's position is fixed and the other four are arranged in 4! = 24 ways. The figure 120 would count rotations separately.
- A120
- B24Correct
- C60
- D12
Explanation
For n persons around a circle, the number of arrangements is (n-1)!. Here (5-1)! = 4! = 24. The value 120 is 5!, which wrongly treats rotations as different arrangements.
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