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    Ok, think I must be missing something really obvious here.

    Question as follows:

    The three events E1, E2 and E3 are defined in the same sample space and P(E1UE2UE3) = 1. The events E1 and E2 are independant. Given that events E1 = 2/3, E2 = 1/4 and E3 = 1/4 find P(E2UE3)

    I've worked it out to be 0;
    P(E2) + P(E3) - P(E2nE3)
    1/4 + 1/4 - 1/16 = 0

    But thats wrong, the answer says it is 1/2. :confused:

    Where is it going wrong. Something to do with 1 & 2 being independant??

    Thanks
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    1 and 2 are indpendent, but it says nothing about 3. Obviously from the answer, it is clear that P(2n3) = 0.

    So you must then proceed to prove that the events E2 and E3 must be mutually exclusive..
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    One other thing, 1/4 + 1/4 - 1/16 isn't 0. Not relevant, but just thought I'd say.
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    (Original post by mockelinho)
    One other thing, 1/4 + 1/4 - 1/16 isn't 0. Not relevant, but just thought I'd say.

    Oh yeah :rolleyes: Too much revision, brain must be asleep!!!
 
 
 
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Updated: April 12, 2006
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