CA Foundation · Quantitative Aptitude · Probability
Five persons, including Anil and Bhavna, are seated at random in a row of 5 chairs. What is the probability that Anil and Bhavna sit next to each other?
The probability is 2/5. There are 120 total seatings; treating the pair as one unit gives 4! = 24 arrangements, doubled to 48 because the two can swap places, so the probability is 48/120 = 2/5.
- A2/5Correct
- B1/5
- C3/5
- D1/10
Explanation
Total arrangements = 5! = 120. Treat Anil and Bhavna as one block: 4! = 24 arrangements, times 2 internal orders = 48. Probability = 48/120 = 2/5. Forgetting the internal order gives 24/120 = 1/5.
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