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Homework Help: Probability mutual exclusive homework problem

  1. Mar 17, 2004 #1
    Given that p(A)=0.6 and p(B)= 0.7 and that A and B are independent, find the probabilty of
    a. A or B
    b. A and B

    I don't understand this because if 2 events are independent, then they are not mutually exclusive. So, A and B does not = 0, but that's all I know and I need A and B to solve for A or B. Help! Thanks
  2. jcsd
  3. Mar 17, 2004 #2


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    Science Advisor

    Re: Probability

    Just multiply the two together.
    (0.6)(0.7) = 0.42

    For this one you have to find the probability of A only, B only, A and B. Then you just add those.
    A only:
    (0.6)(1-0.7) = 0.18
    B only:
    (1-0.6)(0.7) = 0.28
    A and B:
    (0.6)(0.7) = 0.42

    Sum of those:
    0.18 + 0.28 + 0.42 = 0.88
    Last edited: Mar 17, 2004
  4. Mar 17, 2004 #3
    Re: Re: Probability

    ¡Muchas gracias! That helped a lot
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