Question: As a student, you probably have noticed a curious phenomenon. In every class, there are some students who zip through exams and turn in their papers while everyone else is still on page 1. Other students cling to their exams and continue working until the very last minute. Have you ever wondered what grades these students get? Are the students who finish first the best in the class or are they simply conceding failure? To answer this question, we carefully observed a recent exam and recorded the amount of time each student spent working and the grade each student received. Following are data for a sample of n = 10 students.
a. Calculate the Pearson correlation between time and grade.
b. Based on the correlation, describe the relationship between time and grade. Do the highest grades go to the students who finish first or last?
Time (in minutes) Exam Grade
54 75
38 91
60 70
44 94
60 76
40 89
57 92
52 81
45 88
49 90