Question

A quality control inspector has drawn a sample of 14 light bulbs from a recent production lot. If the number of defective bulbs is 1 or less, the lot passes inspection. Suppose 20% of the bulbs in the lot are defective. What is the probability that the lot will pass inspection? Round your answer to four decimal places.

Answer 1

Let's write the given information

sample size = n = 14

Probability of getting defectives in the lot = p = 0.20,

Let's used binomial distribution to find the probability that the lot will pass inspection

If we find at most 1 defective then the lot is OK

If X is the number of defectives in the lot then we want to find P(X <= 1)

Let's used "=BINOMDIST(x,n,p,1)" this binomial command to find the less than or equal probabilities.

P( X <= 1) = =BINOMDIST(1,14,0.2,1) = 0.1979