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    I = 'that line you see when representing the probability of one event happening on the condition that the other has happened'

    Given P(RIS) = 0.5, P(RIS') = 0.4 AND P(S) = 0.6, find:

    a) P(R) b) P(SIR) c) P(S'IR) d) P(S'IR')


    a) P(R) = 0.46

    b) P(SIR) = 0.652

    c)
    P(S'IR) = 0.348

    d) P(S'IR') = ? (answer in the book says 4/9)


    Any help would be appreciated.

    Thank you
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    Does the "I" stand for intersection?

    P(S'IR') = Anything outside P(R) and P(S). So 1 - P(RuS) = P(S'IR').
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    (Original post by Mambo No. 5)
    I = 'that line you see when representing the probability of one event happening on the condition that the other has happened'

    Given P(RIS) = 0.5, P(RIS') = 0.4 AND P(S) = 0.6, find:

    a) P(R) b) P(SIR) c) P(S'IR) d) P(S'IR')


    a) P(R) = 0.46

    b) P(SIR) = 0.652

    c)
    P(S'IR) = 0.348

    d) P(S'IR') = ? (answer in the book says 4/9)


    Any help would be appreciated.

    Thank you
    you could've written it like this:

    P(A | B)
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    (Original post by Mambo No. 5)

    d) P(S'IR') = ? (answer in the book says 4/9)


    Any help would be appreciated.

    Thank you
    To find P(S'|R'), you need P(S'nR') which is equal to 1-P(SuR), with the obvious meanings to 'n' and 'u'.
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    (Original post by Dream Eater)
    Wow, that was a communication breakdown. To OP: you can use the ' | ' key on your keyboard to avoid confusion. About the question, I may be wrong but I think there is one piece of information missing. I don't think it is solvable for P(R) as it is. Have you missed anything out?

    In fact you can even prove that not just one answer exists. If R,S are independent events then P(R) = 0.5 works just fine as well.
    Yeah I had know idea I = l or /.

    Doh :P
 
 
 
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