In: Statistics and Probability
A fast-food restaurant manager wants to see the average bill per car passing through the drive-thru increase. Historically, cars spend an average of $12.39. After implementing the new process employees must follow for each car in the drive-thru, the manager randomly selects 40 cars and finds the mean bill is $12.87 with a standard deviation of $3.92. Does this sample evidence suggest the new process results in a higher ticket price per car? Use a 0.05 level of significance.