The local regional transit authority of a large city was interested in determining the mean commuting time for workers who drove to work. They selected a random sample of 125 residents of the metropolitan region and asked them how long they spent commuting to work (in minutes). A 95% confidence interval was constructed and reported as (27.74, 30.06). Interpret the interval in the context of this problem. 2. A long distance telephone company recently conducted research into the length of calls (in minutes) made by customers. In a random sample of 45 calls, the sample mean was minutes and the standard deviation was s 5. 2 minutes. (a) Find a 95% confidence interval for the true mean length of long distance telephone calls made by customers of this company. x 1 . 68