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Homework Help: Pls. Help

  1. Oct 22, 2007 #1
    There are three urns.

    1. The first contains 2 white and 4 black cards
    2. The second contains 8 white and four black cards
    3. The third contains 1 white and 3 black card.

    If one card is selected from each urn, find the probability that exactly 2 white cards are drawn"
  2. jcsd
  3. Oct 22, 2007 #2


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    You need to show some work before we can help you. What thoughts do you have on the problem? Have you done any examples like this before?
  4. Oct 22, 2007 #3


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    P(exactly two white cards) = P(WWB) + P(WBW) + P(BWW) = P(at least two white cards) - P (WWW).

    You'll need to show some work if you want to get anything useful out of us. :p
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