question 1

A random sample of 14 subjects was asked to perform a given task. The time in seconds it took each of them to complete the task is recorded below. 45, 34, 37, 50, 34, 30, 25, 29, 39, 50, 39, 33, 49, 46 Send data to calculator If we assume that the completion times are normally distributed, find a 95% confidence interval for the true mean completion time for this task. Give the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) Lower limit: Il X 5 Upper limit:A researcher collected sample data for 15 middleaged women. The sample had a mean serum cholesterol level (measured in milligrams per one hundred milliliters) of 188.6, with a standard deviation of 7.5. Assuming that serum cholesterol levels for middleaged women are normally distributed, find a 99% confidence interval for the mean serum cholesterol level of all women in this age group. Give the lower limit and upper limit of the 99% confidence interval. Cam.r your intermediate computations to at least three decimal places. Round your answers to one decimal place. [If necessary, consult a list of formulas.) Lower limit: III x b 9 Upper limit: ll