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Homework Help: Poisson distribution problem

  1. Jan 27, 2005 #1
    so flaws in metal produced by high temperatures occure at a rate of 1 per 10 square feet. what is the probability that there is 3 or more flaws in a 8 x 5 feet.

    ok, so I know we need to use poisson disstribution on this, e^-np * np^k/k!.

    howver, I dont know my np.

    so 1 per 10 square feet means 1 per 10 x 10 feet....maybe we can say this is the same as .1 per 1 x 1 feet.

    so how do I put this in terms of 8 x 5 feet?
     
  2. jcsd
  3. Jan 27, 2005 #2
    8*5 = 40 square feet...
    you have 1 per 10 square feet.... that's means....

    even a 10 years old kids can do this problem...

    what grade are you in? I don't realize middle school teachers start teaching poisson equation to the 7th grader.....
     
  4. Jan 27, 2005 #3

    haha...whoops, wasn't thinking about this...I got it...haha
     
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