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Math Help - Help with Expected Values

  1. #1
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    Help with Expected Values

    A coin is thrown six times.
    What is the expected total number of tails, given the last throw is a head.

    Any ideas on how to do this?

    Thanks in advance
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  2. #2
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    Re: Help with Expected Values

    you can do it with a tree diagram.

    also since you have .5 chance of getting either tails or heads

    it would be:

    E(X) = 1/2 * ( 1++2+3+4+5+6) -----> since you have 6 trials

    which is equals to = E(x) = 10.5
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  3. #3
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    Re: Help with Expected Values

    Quote Originally Posted by hollymxox View Post
    you can do it with a tree diagram. also since you have .5 chance of getting either tails or heads
    it would be: E(X) = 1/2 * ( 1++2+3+4+5+6) -----> since you have 6 trials
    which is equals to = E(x) = 10.5
    @hollymxox
    If you are going to try to help, please at least understand the question.
    Look that how absurd your above answer is.
    There are only six trials. So how can the expected value be 10.5?
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