Question

A machine produces an average of 20% defective bolts.a batch is accepted if a sample of 5 bolts taken from that batch contains no defective and rejected if the sample contain 3 or more defectives.in other cases,a second sample is taken.what is the probability that the second is requuired?explain solustion

Answer 1

According to question
20% bolts are defective
Thus probability of defective bolts = 20/100 = 1/5

Thus according to question

Probability that batch doesnt contain any defective bolt = 5/80
                                                                                       = 1/16
And
Probability that batch contains three defective balls = 3/20