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Math Help - probability

  1. #1
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    probability

    A fair die is rolled six times. If on the nth roll, 1<=n<=6 the result is n, we call it a hit. What is the prob. that we get at least one hit in the six rolls.


    Now, do the same but with two dice, and rolling the twelve times. What is the probability that we get at least one hit?
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  2. #2
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    Quote Originally Posted by Andreamet View Post
    A fair die is rolled six times. If on the nth roll, 1<=n<=6 the result is n, we call it a hit. What is the prob. that we get at least one hit in the six rolls.


    Now, do the same but with two dice, and rolling the twelve times. What is the probability that we get at least one hit?
    Instead find the probability of getting no hits. Which means the first roll can be: 2,3,4,5,6. The second can be: 1,3,4,5,6 and so on. Now compute the probability.
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  3. #3
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    Quote Originally Posted by ThePerfectHacker View Post
    Instead find the probability of getting no hits. Which means the first roll can be: 2,3,4,5,6. The second can be: 1,3,4,5,6 and so on. Now compute the probability.
    so should we multiply these probabilities? ie. 1-(5/6)^6 and 1-(11/12)^12?

    thanks!
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    Quote Originally Posted by Andreamet View Post
    so should we multiply these probabilities? ie. 1-(5/6)^6
    Yes
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  5. #5
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    Quote Originally Posted by ThePerfectHacker View Post
    Instead find the probability of getting no hits. Which means the first roll can be: 2,3,4,5,6. The second can be: 1,3,4,5,6 and so on. Now compute the probability.
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