A man has 3 children. Their probabilities of passing an exam are 1/2, 1/3, 1/4. What will be the

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15 Oct 2010 Find the probability?

A man has 3 children. Their probabilities of passing an exam are 1/2, 1/3, 1/4.
What will be the probability that at least 1 of them could pass the exam?

OPtion

1) 2/3
2) 1/2
3) 3/4
4) 3/5
5) 2/7
6) 1/5
7) 1/6
8) 2/5
9) 3/7
10) 2/9

Solution

The probability of failure of all = [1-(1/2)][1-(1/3)][1-(1/4)] = 1/4
Hence answer = [1-(1/4)] = 3/4

Correct Option: 3 Best Solution (2)