I would not use Excel. Just use the formula for a Poisson distribution... once. The carpet has 126 square feet and the probability of flaws per square foot is p = 1/300. If m is the number of flaws, the probability of m flaws in n = 126 square feet is given by
the Poisson distribution formula.
P(m) = [a^m*e^-a]/m!
where, in this case,
a = n*p = 126/300 = 0.42
P(3) = (0.42)^3*e^-0.42/3! = 0.008
P(2) = (0.42^2*e-0.42/2! = 0.058
P(1) = (0.42)*e^-0.42/1 = 0.275
P(0) = (0.42)^0*e^-0.42/1 = 0.657
The probability you are looking for is
P(0)
Flaws in a carpet tend to occur with a Poisson distribution at a rate of one flaw every 300 square feet. What is the probability that a carpet that is 9 feet by 14 feet contains no flaws?
Probability =
how would you set it up in excel?
2 answers
=POISSON(0,0.42,FALSE)
1 answer