1. If a normally distributed sample of size n = 16 prod uces a 95% confidence interval for µ.. that ranges from 44.7 to 49.9, what are the values of y and s?
2. Two samples, each of size n, are taken from a nonnal distribution with unknown mean µ, and unknown standard deviation a. A 90% confidence interval for µ.. is constructed with the first sample, and a 95% wnfidence interval for µ, is constructed with the second. Will the 95% confidence interval necessarily be longer than the 90% confidence interval? Explain.
3. Revenues reported last week from nine boutiques franchised by an international clothier averaged $59,.540 with a standard deviation of $6,860. Based on those figures, in what range might the company expect to find the average revenue of all of its boutiques?