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The probability that event A occurs is 0.4, and the probabil [#permalink]
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Updated on: 28 Mar 2018, 04:13
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The probability that event A occurs is 0.4, and the probability that events A and B both occur is 0.25. If the probability that either event A or event B occurs is 0.6, what is the probability that event B will occur? A. 0.05 B. 0.15 C. 0.45 D. 0.50 E. 0.55
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Originally posted by shrive555 on 26 Dec 2010, 18:47.
Last edited by abhimahna on 28 Mar 2018, 04:13, edited 1 time in total.
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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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26 Dec 2010, 21:42
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P(A or B) = P (A) + P(B)  p(a n b) 0.6= 0.4 + P(B)  0.25 P(B) = 0.45
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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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26 Dec 2010, 23:30
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P(AandB) = pA + pB  p(AintersectionB) 0.6= 0.4 + p(B)  0.25 = 0.45
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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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27 Dec 2010, 03:29
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you can state both equations only if they are independent from each other ...



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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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10 Aug 2013, 05:33
hirendhanak wrote: P(A or B) = P (A) + P(B)  p(a n b) 0.6= 0.4 + P(B)  0.25 P(B) = 0.45 Hi. Can u tell me wat is P(AandB)???? Please clear my doubt. regards, Rrsnathan.



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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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10 Aug 2013, 05:59
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rrsnathan wrote: hirendhanak wrote: P(A or B) = P (A) + P(B)  p(a n b) 0.6= 0.4 + P(B)  0.25 P(B) = 0.45 Hi. Can u tell me wat is P(AandB)???? Please clear my doubt. regards, Rrsnathan. P(A and B)= probability both events (A,B) occur= P(A)*P(B). Hope this clear your doubt
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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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10 Aug 2013, 14:10
shrive555 wrote: The probability that event A occurs is 0.4, and the probability that events A and B both occur is 0.25. If the probability that either event A or event B occurs is 0.6, what is the probability that event B will occur? 0.05 0.15 0.45 0.50 0.55 P(A) = .40 P(A and B) = P(A) * P(B) = .25 1 P(A or B) = P (A) + P(B) = .60 2 Both 1 & 2 give different results. 1 => P(B) = \(.25/P(A)\) = 0.62 2=> P(B) = .60  .40 = .20 whats going wrong ...i don;t know The only correction you need is to minus... P(A or B) = P (A) + P(B)  P(A) * P(B) = or, 0.60 = 0.4 +p(B)  0.25 so, p(B) = 0.45 (C) we all make mistake....don't worry about it...
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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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12 Oct 2017, 20:30
shrive555 wrote: The probability that event A occurs is 0.4, and the probability that events A and B both occur is 0.25. If the probability that either event A or event B occurs is 0.6, what is the probability that event B will occur? A. 0.05 B. 0.15 C. 0.45 D. 0.50 E. 0.55 P(A) = .40 P(A and B) = P(A) * P(B) = .25 1 P(A or B) = P (A) + P(B) = .60 2 Both 1 & 2 give different results. 1 => P(B) = \(.25/P(A)\) = 0.62 2=> P(B) = .60  .40 = .20 whats going wrong ...i don;t know If A and B are overlapping events then P (A or B) = P(A) + P(B)  P(A and B) C



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Re: The probability that event A occurs is 0.4, and the probabil [#permalink]
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12 Oct 2017, 20:36
shrive555 wrote: The probability that event A occurs is 0.4, and the probability that events A and B both occur is 0.25. If the probability that either event A or event B occurs is 0.6, what is the probability that event B will occur? A. 0.05 B. 0.15 C. 0.45 D. 0.50 E. 0.55 P(A) = .40 P(A and B) = P(A) * P(B) = .25 1 P(A or B) = P (A) + P(B) = .60 2 Both 1 & 2 give different results. 1 => P(B) = \(.25/P(A)\) = 0.62 2=> P(B) = .60  .40 = .20 whats going wrong ...i don;t know Another way of looking at this is that both events are overlapping events A and B can occur at the same time  this is basically the same as Total= A + B both > is the same thing as saying P(A or B)= P(A) + P(B) P(A and B) This is one application of the overlapping set formula to probability




Re: The probability that event A occurs is 0.4, and the probabil
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