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Homework Help: Need help with probability

  1. Dec 12, 2004 #1
    Need help with probability!!!

    Can someone help me solve this problem?

    Geri is going door-to-door in a neighbourhood where there are 14 blue houses, 18 white houses, and 22 houses with other colours. There are equal numbers of odd and even numbered houses of each colour. Geri is dropped off at random. What is the probability that the first house she visits will be white and even-numbered?
  2. jcsd
  3. Dec 12, 2004 #2


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    Since there are as much even-numbered as there are odd-numbered, the probability that her first house be even-numbered is one out of two.

    ""Additionally"", there are 18 white houses out of 14+18+22 = 54 houses. So her chances of hitting a white house are of 18/54 = 1/3.

    So the probability that she gets the two combined (white AND even-numbered) is therefor of (1/2)(1/3) = 1/6.
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