if the probability that event A will occur is 0.5 what's the probability that event B will occur?
1) the probability that both A and B will occur is 0.3
2) the probability that at least one of the events will occur is 0.8
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life is a test
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IMO Drickjan wrote:if the probability that event A will occur is 0.5 what's the probability that event B will occur?
1) the probability that both A and B will occur is 0.3
2) the probability that at least one of the events will occur is 0.8
1. p(a) * p(b) = 0.3 -> 0.5 * p(b) = 0.3 -> suff
2. p(a) + p(b) + p(ab) = 0.8 = 0.5 + p(b) + 0.5*p(b) -> suff.
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Stuart@KaplanGMAT
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Where's the question from? Did you copy it verbatim?rickjan wrote:if the probability that event A will occur is 0.5 what's the probability that event B will occur?
1) the probability that both A and B will occur is 0.3
2) the probability that at least one of the events will occur is 0.8
I'm sure that D is the intended answer to the question - but in order for either statement to be useful, we need to know that A and B are independent events.
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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Stuart@KaplanGMAT
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It means that I think the question is worded very poorly; in its current form the answer should be E (not enough information), but my guess it that whoever wrote the question intended each statement to be sufficient alone.2010gmat wrote:Stuart when you say D is the intended answer...does it mean that its a trap or does it mean that D is the right answer
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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