A trucking company wants to find out if their drivers are stillalert after driving long hours. So, they give a test for alertnessto two groups of drivers. They give the test to 400 drivers whohave just finished driving 4 hours or less and they give the testto 585 drivers who have just finished driving 8 hours or more. Theresults of the tests are given below.
Passed Failed
Drove 4 hours or less 310 90
Drove 8 hours or more 415 170
Is there is a relationship between hours of driving andalertness? (Do a test for independence.) Test at the 1 % level ofsignificance.
