Question: A company is having a new corporate website developed. In the final testing phase the download time to open the new home page is recorded for a large number of computers in office and home settings. The mean download time for the site is 2.5 seconds. Suppose that the download times for the site are normally distributed with a standard deviation of 0.5 seconds. If you select a random sample of 30 download times:
(a) What is the probability that the sample mean time is less than 2.75 seconds?
(b) What is the probability that the sample mean time is between 2.70 and 2.90 seconds?
(e) The probability is 80% that the sample mean time is between what two values symmetrically distributed around the population mean?
(d) The probability is 95% that the sample mean time is less than what value?