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Math Help - math contest problem on probability.

  1. #1
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    math contest problem on probability.

    Two fair coins are to be tossed once. For each head that results, one fair die is to be rolled. What is the probability that the sum of the die rolls is odd? ( Note that if no die is rolled the sum is 0)

    I could think of the cases

    HH the sum to be odd is 18/36
    HT one die rolled 3/6 is odd
    TH one die rolled 3/6 is odd
    TT

    I'm stuck from here....

    Vicky.

    My knowledge of probability is very basic so could this please be explained as easy as possible?
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  2. #2
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    Quote Originally Posted by Vicky1997 View Post
    Two fair coins are to be tossed once. For each head that results, one fair die is to be rolled. What is the probability that the sum of the die rolls is odd? ( Note that if no die is rolled the sum is 0)

    I could think of the cases

    HH the sum to be odd is 18/36
    HT one die rolled 3/6 is odd
    TH one die rolled 3/6 is odd
    TT

    I'm stuck from here....

    Vicky.

    My knowledge of probability is very basic so could this please be explained as easy as possible?
    Pr(HH) = 1/4, Pr(HT) = 1/4 .....

    So the answer will be (1/4)(18/36) + (1/4)(3/6) + .... = ....
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  3. #3
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    Quote Originally Posted by mr fantastic View Post
    Pr(HH) = 1/4, Pr(HT) = 1/4 .....

    So the answer will be (1/4)(18/36) + (1/4)(3/6) + .... = ....

    Then it would be 1/8 + 1/8 + 1/8 = 3/8

    Thank you!!
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