Researchers at Purdue University and Wichita State University found that airlines are doing a better job of getting passengers to their destinations on time (Associated Press, April 2,...

Researchers at Purdue University and Wichita
State University found that airlines are doing a better job of getting passengers to
their destinations on time (Associated Press, April 2, 2012). AirTran Airways and
Southwest Airlines were among the leaders in ontime arrivals with both having 88%
of their flights arriving on time. But for the 12% of flights that were delayed, how
many minutes were these flights late? Sample data showing the number of minutes
that delayed flights were late are provided in the sheet named AirDelay. Data are
shown for both airlines.
(a) Formulate the hypotheses that can be used to test for a difference between the
population mean minutes late for delayed flights by these two airlines.
(b) What is the sample mean number of minutes late for delayed flights for each of
these two airlines?
(c) Using a 0.05 level of significance, what is the p-value and what is your conclusion?