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    Please help me understand:
    4) the number of surface flaws in plastic panels used in the interior of automobiles has a Poisson Distribution with a mean of 0.05 flaws per square foot of plastic panel. Assume an automobile interior contains 10 square feet of plastic panel


    a)Probability that there are no surface flaws in an auto interior = 0.6065


    b) If 10 cars are sold to a rental company, what is the probability that none of the 10 cars has any surface flaws?


    The solution given by my lecturer is: P(Y=10) = 10C10(0.6065)^10(0.3935)^0
    = 0.0067


    HOWEVER , I thought that the binomial equation is nCx(P)x(q)n-x


    I would like to know why is "x" 10? when the question is asking for cars with 0 surface flaws ?


    THis is what i did .
    =10C0(0.6065)^0(0.3935)^10


    ...


    What did i misunderstand here?
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    In your solution, you're finding the probability of zero cars having zero flaws.
    Whereas the question wants 10 cars with zero flaws, so you use 10C10. It's sort of a bit of word play, easy to get caught out.
 
 
 
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