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    The addition rule is easy to do when its P(AUB) but Im having immense difficulty when its P(A'UB) or P(AUB'). I have the solution bank and have looked the Venn diagrams, I see which numbers they use but I cant seem to understand why.

    Can somebody please help because Ive been stuck on it for a day now!
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    Can you give an example of what you've been stuck on?
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    Goodness wasted so much time.

    P(A'UB) would open up as

    P(A') + P(B) - P(A'nB)

    To get P(A'), simply '1 - P(A)' and P(A'nB) is easily read off from the Venn diagram.
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    (Original post by FirstDiscovery)
    Goodness wasted so much time.

    P(A'UB) would open up as

    P(A') + P(B) - P(A'nB)

    To get P(A'), simply '1 - P(A)' and P(A'nB) is easily read off from the Venn diagram.
    Yes, ok. But what about it don't you understand?

    Do you understand why  P(A^c) = 1 - P(A)

    Or why  P(A^c \cap B) = P(A^c) + P(B) - P(A^c \cap B) ?
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    (Original post by ekudamram)
    Yes, ok. But what about it don't you understand?

    Do you understand why  P(A^c) = 1 - P(A)

    Or why  P(A^c \cap B) = P(A^c) + P(B) - P(A^c \cap B) ?
    Thanks for bringing those up as I ran into them earlier. The book doesnt show everything.
 
 
 
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