Out of a class of 40 students, 32 passed the course. Of those that passed, 24 had taken the prerequisite course, while of those that failed, only 1 had taken the prerequisite. Test the hypothesis that...

Out of a class of 40 students, 32 passed the course. Of those that passed, 24 had taken the prerequisite course, while of those that failed, only 1 had taken the prerequisite. Test the hypothesis that taking the prerequisite course did not help to pass the course.

A machine has a record of producing 80% excellent, 18% good, and 2% unacceptable parts. After extensive repairs, a sample of 200 produced 157 excellent, 42 good, and 1 unacceptable part. Have the repairs changed the nature of the output of the machine?