In a random selection of two people from a group of five-A, B, C, D, and E-what
is the probability of selecting A and B?
(A)
2/5
(B)
1/5
(C)
1/10
(D)
1/15
(E)
1/20
The correct answer is [spoiler]c
i thought the probability was 1/20 but it didn't match the answer ,,,can any1 explain me !!![/spoiler]
problem
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- vineeshp
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I guess you multiplied 1/5 * 1/4. That would have been right if the question said, probability of selecting B given A is already selected. Here 2 ppl are selected.
No of ways of selecting 2 ppl from 5 = 5C2 = 10
No of ways of selecting A and B = 1 (2C2)
Hence probability = 1/10.
PS: "explain me" is wrong language.
No of ways of selecting 2 ppl from 5 = 5C2 = 10
No of ways of selecting A and B = 1 (2C2)
Hence probability = 1/10.
PS: "explain me" is wrong language.
Vineesh,
Just telling you what I know and think. I am not the expert.
Just telling you what I know and think. I am not the expert.