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Math Help - dice questions

  1. #1
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    dice questions

    I have these two questions and just want to make sure they are right:

    5.6 Determine the probability of the following:

    a. If three dice are rolled, that all will be odd = 1/2

    b. If two coins are flipped, that they both will land the same = 1/2

    Can someone please tell me if this is correct. Thanks.
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  2. #2
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    Quote Originally Posted by papa_chango123 View Post
    I have these two questions and just want to make sure they are right:

    5.6 Determine the probability of the following:

    a. If three dice are rolled, that all will be odd = 1/2

    b. If two coins are flipped, that they both will land the same = 1/2

    Can someone please tell me if this is correct. Thanks.
    You are incorrect in both.


    a. If three dice are rolled, that all will be odd

    There is 1/2 chance that one die will land odd.

    So for three dice its: \frac{1}{2}\times\frac{1}{2}\times\frac{1}{2}=\fra  c{1}{8}

    So it's only a 1/8 chance

    Now you try the coins
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  3. #3
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    Ok I understand how you got the dice but on the coins here is my logic:

    The coins flipped could be 4 probable:

    HH, HT, TT, TH

    So they could both land the same 2 times out of 4. Would that not be

    2/4 = 1/2?
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  4. #4
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    Quote Originally Posted by papa_chango123 View Post
    Ok I understand how you got the dice but on the coins here is my logic:

    The coins flipped could be 4 probable:

    HH, HT, TT, TH

    So they could both land the same 2 times out of 4. Would that not be

    2/4 = 1/2?
    Yes it would be (I tend to misread questions)

    Just for you to think of it mathwise:

    Whatever the first coin lands on will work, but the other coin has only 1/2 chance of landing the same way.

    In math thats: 1\times\frac{1}{2}=\frac{1}{2}
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  5. #5
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    Thanks for the help
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