1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Conditional Probability (ii)

  1. Dec 16, 2009 #1
    box A contains 2 red balls,
    box B contains 2 white balls,
    box C contains 1 red ball and 1 white ball,

    A box is selected at random (with equal probabilities) and one ball is taken at random from that box.

    (i) Compute the probability of selecting a white ball using Bayes Rule.

    A(1/3) _____ Red(1/6)
    .........|____ Red(1/6)

    B(1/3)______White(1/6)
    ........|_____White(1/6)

    C(1/3)______Red(1/6)
    ........|_____White(1/6)

    so.. P(White) = [(1/3)*(1/6)] + [(1/3)*(1/6)] + [(1/3)*(1/6)]
    = 1/6

    Correct?


    (ii)Compute the conditional probability that B has been selected given that the ball is white.

    P(B|White) = P(B intersect White) / P(White)

    what is my P(B intersect White)?
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted