Chapter 4.3, Problem 4.47ACB

Working on summer vacation. Recall (Exercise 3.13, p. 145) that a Harris Interactive (July 2013) poll found that 22% of U.S. adults do not work at all while on summer vacation. In a random sample of 10 U.S. adults, let x represent the number who do not work during summer vacation.

1. a. For this experiment, define the event that represents a “success.”
2. b. Explain why x is (approximately) a binomial random variable.
3. c. Give the value of p for this binomial experiment.
4. d. Find P (x = 3).
5. e. Find the probability that 2 or fewer of the 10 U.S. adults do not work during summer vacation.