Understanding Basic Statistics 6th Edition by Charles Henry Brase,Corrinne Pellillo Brase

Exercise 44

In Problems 13-19, assume that the population of x values has an approximately normal distribution.
Hospitals: Charity Care What percentage of hospitals provide at least some charity care The following problem is based on information taken from State Health Care Data: Utilization, Spending and Characteristics (American Medical Association). Based on random sample of hospital reports from eastern states, the following information was obtained (units in percentage of hospitals providing at least some charity care).
57.1 56.2 53.0 66.1 59.0 64.7 70.1 64.7 53.5 78.2
(a) Use a calculator with mean and sample standard deviation keys to verify that
62.3% and s 8.0%.
(b) Find a 90% confidence interval for the population average of the per­centage of hospitals providing at least some charity care.
(c) Interpretation What does the confidence interval mean in the context of this problem