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Probability simple question

  1. Jan 28, 2012 #1

    As the question says the probability that both of them were longer than 24.5 minutes i'd of thought it would be in the 24-29 row, so that means 8/55 * 7/54, but the answer is 11/55 * 10/54, where did they get 11 from?
  2. jcsd
  3. Jan 28, 2012 #2


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    How many ways are to choose 2 from the over 24.5 minute group? How many ways are there to choose 2 overall?
  4. Jan 28, 2012 #3
    oh god im stupid, thank you.
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