IMO Cdanjuma wrote:If events A and B are independent, is the probability of both events occuring less than 0.4?
1.The probability of event A occuring is 0.5
2.The probability of event B occuring is 0.3
Probability
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Source: Beat The GMAT — Data Sufficiency |
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shovan85
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We are asked about the possibility of both events. So P = P(A)*P(B)
1. P(A) = 0.5, we do not have P(B), and P(B) can be 1 or 0.3 then P can be 0.5 or 0.15
Then this is not sufficient to know whether P >0.4
2. P(B)=0.3<0.4, moreover P(A) always <= 1
Then P(B)*P(A) <=0.3
Then P<0.4
Thus 2 is suf.
Pick B.
1. P(A) = 0.5, we do not have P(B), and P(B) can be 1 or 0.3 then P can be 0.5 or 0.15
Then this is not sufficient to know whether P >0.4
2. P(B)=0.3<0.4, moreover P(A) always <= 1
Then P(B)*P(A) <=0.3
Then P<0.4
Thus 2 is suf.
Pick B.
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is B the answer?danjuma wrote:If events A and B are independent, is the probability of both events occuring less than 0.4?
1.The probability of event A occuring is 0.5
2.The probability of event B occuring is 0.3
Pa < 1 and Pb=0.3 thus Pa*Pb<o.3 thus B is sufficient
