Discussion:
Q: The mean waiting time for the drive-through window of a fast-food franchise is believed to be 3.7 minutes. A manager wants to check the time at her particular restaurant. A sample of 75 customers is selected and the sample mean waiting time is 3.57 minutes with a sample standard deviation of 0.8 minutes. Is there evidence that the waiting time at this particular restaurant is less than 3.7 minutes? Use a 1% level of significance. What is your conclusion?