For Exercises 27–34, answer the following questions:

  1. Calculate .
  2. Find for a confidence interval for with 95% confidence.
  3. Construct and interpret a 95% confidence interval for .

Question 8.31

31. A random sample of with sample mean is drawn from a population in which .

8.1.31

(a) 1 (b) 1.96 (c) (18.04, 21.96). We are 95% confident that the population mean lies between 18.04 and 21.96.