Your Chemistry professor last semester lost your final exam. He therefore used your total points earned prior to the exam in the class (X) to predict your final exam grade (Y). He knows the correlation between his students' total points before the exam (X) and final exam grade (Y) is +.65. Your point total before the final was 280. The mean point total for all students in the class before the final was 250 with a standard deviation of 30. The mean on the final exam for all students in the class was 70 with a standard deviation of 10. (You may find it helpful to work through problem 2.49 in your textbook practice problems before working this problem as they are quite similar).
a. What is the slope and intercept for the least squares equation he would use to predict your final exam grade (Y) from your total points prior to the final (X)?
b. What would he predict your final exam grade to be?
c. You don't believe this method accurately predicts your final exam performance. Calculate the coefficient of determination and use it to argue that his prediction is not accurate.