On average 6 percent of all persons who are given a breathal

On average, 6 percent of all persons who are given a breathalyzer test by the state police pass the test (blood alcohol under 0.08 percent). Suppose that 200 breathalyzer tests are given. (a) What is the expected number who pass the test?

Solution

p=prob of pasing the test = 0.06

n = 200

As there are two outcomes, X no of passes is binomial

Expected value= np

= 200(0.06)

= 12