Medication Usage In a survey of 3005 adults aged 57 through 85 years, it was found that 81.7% of them used at least one prescription medication (based on data from “Use of Prescription and Over-the-Counter Medications and Dietary Supplements Among Older Adults in the United States,” by Qato et al., Journal of the American Medical Association, Vol. 300, No. 24).
a. How many of the 3005 subjects used at least one prescription medication?
b. Construct a 90% confidence interval estimate of the percentage of adults aged 57 through 85 years who use at least one prescription medication.
c. What do the results tell us about the proportion of college students who use at least one prescription medication?
Determining Sample Size. In Exercises 29–36, use the given data to find the minimum sample size required to estimate a population proportion or percentage.