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Math Help - Fair die probability

  1. #1
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    Fair die probability

    I'm having trouble with this problem:

    A fair die is rolled over and over again until the sum of all the numbers obtained is greater than 4. What's the probability that this takes one roll, or two rolls, or three rolls, or four rolls, or five rolls? (Exactly 1, 2, etc. rolls)
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  2. #2
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    Quote Originally Posted by mhitch03 View Post
    I'm having trouble with this problem:

    A fair die is rolled over and over again until the sum of all the numbers obtained is greater than 4. What's the probability that this takes one roll, or two rolls, or three rolls, or four rolls, or five rolls? (Exactly 1, 2, etc. rolls)
    List the favourable outcomes for one roll, two rolls etc. and calculate the probability of these outcomes. eg. For one roll the favourable outcomes are getting a five or getting a six. Therefore the probability of taking one roll is 1/6 + 1/6 = 1/3.

    If you need more help, please post what you've done and say where you get stuck.
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