Answer Happy

A simple random sample with n 55 provided a sample mean of 27.5 and a sample standard deviation of 4.4. (Round your answers to one decimal place.) (a) Develop a 90% confidence interval for the population mean.. 27.50 x to 29.49 X (b) Develop a 95% confidence interval for the population mean. 27.31 x to 29.68 (c) Develop a 99% confidence interval for the population mean. 26.91 x to 30.08 (d) What happens to the margin of error and the confidence interval as the confidence level is increased? As the confidence level increases, there is a smaller margin of error and a wider confidence interval. O As the confidence level increases, there is a larger margin of error and a more narrow confidence interval As the confidence level increases, there is a smaller margin of error and a more narrow confidence interval. As the confidence level increases, there is a larger margin of error and a wider confidence interval.