Question

A new advertising program involves placing small screens on the back of taxi front seats in order to run several advertisements continuously. The theory is that riders give their undivided attention to these ads during the entire trip. To understand the potential of the advertising program, advertisers would like to first learn about the length of time of taxi rides. Random samples of the taxi ride times (in minutes) in two cities were obtained. Please assume that the distributions are normal. The summary data are given in the following table. You will not need to use the information from all the rows. Please provide three decimal places for all work and answers unless explicity mentioned otherwise.

Length of Taxi Ride (minutes)	n	x̄	s
San Diego	28	20.322	6.191
Phoenix	28	15.32	5.773
San Diego - Phoenix	28	5.002	8.117

test statistic = 3.126773

d) Calculate the 99% confidence interval for the mean.
(  ,  )

(1 pt.) Interpret the interval calculated above. In addition to the interpretation, please state the critical value

Answer 1