1. Newsweek (November 23, 1992) reported that 40% of all U.S. employees participate in "self-insurance" health plans (p = .40).
a. In a random sample of 100 employees, what is the approximate probability that at least half of those in the sample participate in such a plan?
b. Suppose you were told that at least 60 of the 100 employees in a sample from your state participated in such a plan. Would you think p = .40 for your state? Explain.
2. The nicotine content in a single cigarette of a particular brand has a distribution with mean 0.8 mg and standard deviation 0.1 mg. If 100 of these cigarettes are analyzed, what is the probability that the resulting sample mean nicotine content will be less than 0.79? less than 0.77?