An inspection procedure at a manufacturing plant involves picking three items at random and then accepting?

an inspection procedure at a manufacturing plant involves picking three items at random and then accepting the whole lot if at least two of the three items are in perfect condition. if in reality 80% of the whole lot is perfect, what is the probability that the lot will be accepted?





(a) .512


(b) .560


(c) .640


(d) .896


(e) .992





*please show how you arrived at your answer.

An inspection procedure at a manufacturing plant involves picking three items at random and then accepting?
Probability of all three being perfect (.8)(.8)(.8) =.512


Probability of two being perfect:


(.2)(.8)(.8) +(.8)(.2)(.8) + (.8)(.8)(.2) =.384


At least two perfect means you add these two up and get .896


So, the answer is (d)