The manager of the SNOWY RESTAURANT recently selected a random sample of 18 customers and kept track of how long the customers were required to wait from the time they arrived at the restaurant until they were actually served dinner. This study resulted from several complaints the manager had received from customers saying that their wait time was unduly long and that it appeared that the objective was to keep people waiting in the lounge for as long as possible to increase the lounge business. The following data were recorded, with time measured in minutes (use as the continuous data): 34 24 43 56 74 20 19 33 55 43 54 34 27 34 36 24 54 39
a. Develop a frequency distribution (using six classes, each with a class width of 10, make the lower limit of the first class 15). Noted: the frequency distribution must be included: frequency, relative requency (%), cumulative frequency.
b. Construct box and whisher diagram