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Homework Help: Stats Question, any help is appreciated

  1. Dec 18, 2004 #1
    I'm working on a question which requires you to understand the difference between Independence and disjoint events. The question is: Suppose 24% of a population have 4 years of college, and 15% are laborers/workers. From this, can you conclude that 0.24 x 0.15 = 0.036=3.6% of the population are laborers or workers who had 4 years of college?

    a) No, because the two events are not mutually exclusive (Disjoint Events).
    b) No, because the two events are not independent.

    My teacher says that technically, the two answers are right, but one explains the question give better than the other. Can anyone explain to me why?
  2. jcsd
  3. Dec 18, 2004 #2
    That's something I have learnt when I am young. I don't think it is a stat. question.
    For 10 people, 1 learnt Eng. ,1 learnt Maths
    Can you conclude that only 1 people have studied before?
  4. Dec 19, 2004 #3
    but then what is the difference between independence and disjoint events?
  5. Dec 19, 2004 #4


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    primaryguns response is completely meaningless- ignore it.

    One of the things you should have learned in statistics is:

    "If A and B are independent events then Prob(A and B)= Prob(A)*prob(B)".

    Thus, "No because A and B are not independent" is more relevant than "No because A and B are not mutually disjoint". It happens that A and B are NOT mutually disjoint but that is not the reason the statement is untrue.
  6. Dec 19, 2004 #5
    OOOO Harsh :-D
  7. Dec 20, 2004 #6


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    Science Advisor

    Hey, it was just a warning to "mikeyman2010".
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