In a survey of U.S. adults, 19% said that they have participated in a clinical trial. You randomly select 200 U.S. adults. Find the probability that the number who have participated in a clinical trial is

(a) no fewer than 30,

(b) more than 40, and

(c) between 35 and 45 inclusive.

In Exercises 19–26, determine whether you can use a normal distribution to approximate the binomial distribution.
If you can, use the normal distribution to approximate the indicated probabilities and sketch their graphs. If you cannot, explain why and use a binomial distribution to find the indicated probabilities. Identify any unusual events. Explain.