Question

It is known that screws produced by a certain company will be defective with a probability of .01 independently of each other. The company sells the screws in packages of 25 and guarantees that, at most, only one of the screws will be defective. If 2 or more screws are defective, the customer is entitled to his or her money back. Using Poisson approximation for binomial distribution, the probability that the company must replace a package is approximately____?

a) 0.01 b)0.1947 c)0.7788 d)0.0264 e)0.2211

Answer 1

d)0.0264

Explanation:

p = 0.01

n = 25

x = 2

By applying binomial distribution

P(x,n) = nCx*px*(1-p)(n-x)

P(x > 2) = 0.026

Therefore, The probability that the company must replace a package is approximately 0.0264