Question: FlightStats, Inc., collects data on the number of flights scheduled and the number of flights flown at major airports throughout the United States. FlightStats data showed 56% of flights scheduled at Newark, La Guardia, and Kennedy airports were flown during a three-day snowstorm (The Wall Street Journal, February 21, 2006). All airlines say they always operate within set safety parameters – if conditions are too poor, they don’t fly. The data in Airline.MTW show a sample of 400 scheduled flights during the snowstorm. Use the chi-square test of independence with a 0.05 level of significance to analyze the data.

a) Give the null and alternative hypothesis.

b) Give the test statistic.

c) Give the P-value.

d) Give the decision of this test.

e) What can we conclude from this significance test?