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Message posted by Kevin C. (via 205.188.197.38) on January 23, 2002 at 1:05 AM (ET)

Hello Im having trouble here. Somewhere down the line I have an error. Would you please help. Would you pelase if possible show your work , so that I may compare my errors with the correct answer. Thank you much in advance.

A supervisor at a large plant believes that the expected number of industrail accidents per month is 3.4 What is the probablity that:
a) 2 accidents occur next month
b) 3 or more accidents next month
c) less then 2 next week

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Re: Stats
Message posted by nancy diehl (via 129.176.151.121) on January 23, 2002 at 12:07 PM (ET)

This is an example of applying the Poisson Probability Distribution formula: (mu^x)*(exp^(-mu))/x!..... hard to write this out, so look up how the formula is written. Your mu is 3.4, exp is the exponential function, e; and lastly, the x is the value you are looking for. So....
a.) Prob(x=2), plug in 2 into your formula and solve. You should get 0.03337
b.) Prob(x>=3)=1-Prob(x <=2) = 1- [Pr(x=0)+Pr(x=1)+Pr(x=2) = 1- (.03337 + .11347 + .19290)
c.) Prob(x<2)=Pr(x=0)+Pr(x=1)= .03337 + .11347

Hope that makes sense.
b.)

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