In a random sample of 50 refrigerators, the mean repair cost was $116.00 and the population standard deviation is $18.60. A 95% confidence interval for the population mean repair cost is (110.84, 121.16).
Change the sample size to n=100. Construct a 95% confidence interval for the population mean repair cost. Which confidence interval is wider? Explain.
Construct a 95% confidence interval for the population mean repair cost.
The 90% confidence interval is (____, _____). (Round to two decimal places as needed.)