Suppose you received a score of 91 out of 100 on exam 1. The mean was 79 and the standard deviation was 8. What score do you need on exam 2 to do equally well, if the mean is 60 and the standard deviation is 12?
A)78
B)91
C)95
D)84

Question

Quizplus · Accepted Answer

To do equally well relative to the other scores, you need to achieve the same z-score. The z-score for exam 1 is (91 - 79) / 8 = 1.5. To achieve the same z-score on exam 2, where the mean is 60 and the standard deviation is 12, you solve for the score: 1.5 = (X - 60) / 12. Solving for X gives X = 1.5 * 12 + 60 = 18 + 60 = 78.

Suppose You Received a Score of 91 Out of 100