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I Can't understand this problem

  1. Oct 3, 2004 #1
    Hi guys i have a problem but i dont know how to start solving this
    can you help?

    We have three events:

    A={The midday temperature in Hirakleio is 25C}
    B={The midday temperature in Athens is 25C}
    C={The maximum of the two midday temperatures in Hirakleio and Athens is 25[degrees]C}
    P(A)=0.3
    P(B)=0.4
    P(C)=0.2

    Find the probability that the minimum temperature between the two midday temperatures is 25C
     
  2. jcsd
  3. Oct 3, 2004 #2
    Duh! seems like a pointless question unless they are defining C as AUB and D as AintersectionB where D is the required event.

    In which case the simple Addition Principle does the job.

    -- AI
     
  4. Oct 3, 2004 #3
    so you say that :
    P(D)=P(AintersectionB)=P(A)+P(B)-P(AUB)?
     
  5. Oct 3, 2004 #4

    HallsofIvy

    User Avatar
    Science Advisor

    No, he DIDN'T say that! That would, in any situation at all, result in negative probabilities!
     
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