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    Quick question, with the equation P(AnB)/P(B), how do you calculate P(AnB)?

    http://www.mei.org.uk/files/papers/s108ju_rfs6.pdf question 6ii, the mark scheme says it's just 0.04/0.9801, which is just P(A)/P(B). I'm very confused, please help.
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    (Original post by Guills on wheels)
    Quick question, with the equation P(AnB)/P(B), how do you calculate P(AnB)?

    http://www.mei.org.uk/files/papers/s108ju_rfs6.pdf question 6ii, the mark scheme says it's just 0.04/0.9801, which is just P(A)/P(B). I'm very confused, please help.
    You mean P(A) / P(C) don't you?

    If you use the formula for P(A|C) in terms of P(A n C) and P(C) and think about what the event A n C actually means (read it to yourself in words) you should be able to see where they've got the numbers from
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    (Original post by davros)
    You mean P(A) / P(C) don't you?

    If you use the formula for P(A|C) in terms of P(A n C) and P(C) and think about what the event A n C actually means (read it to yourself in words) you should be able to see where they've got the numbers from
    well yeah for the question. A and B were just arbitrary, they didn't relate to the question

    I eventually managed to figure that one was a subset of the other, but thank you anyway
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    aw man I was stalking you and I saw this thread and thought 'ah yes my time has come'

    I did S1 last year c;
 
 
 
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