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Question
It is given that 5% of the electric bulbs manufactured by a company are defective. Using poisson distribution find the probability that a sample of 120 bulbs will contain no defective bulb
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Solution
P(defective bulbs) = `5/100`
n = 120
The value of mean λ = np = `120 xx 5/100`
λ = 6
Hence, x follows possion distribution with P(x) = `("e"^(-lambda) lambda^x)/(x!)`
(x = 0) = `("e"^(-6) (6)^0)/(0!) = "e"^-6`
= 0.0025
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