Fourteen percent of noninstitutionalized U.S. adults smoke cigarettes.

After randomly selecting ten noninstitutionalized U.S. adults, you ask them whether they smoke cigarettes. Find the probability that the first adult who smokes cigarettes is

(a) the third person selected,

(b) the fourth or fifth person selected, and

(c) not one of the first six persons selected.

In Exercises 21–26, find the indicated probabilities using the geometric distribution, the Poisson distribution, or the binomial distribution. Then determine whether the events are unusual. If convenient, use a table or technology to find the probabilities.