Question

Jenny has five exam scores of 67, 72, 84, 80, and 82 in her biology class. What score does she need on the final exam to have a mean grade of 80? Round your answer to two decimal places, if necessary. (All exams have a maximum of 100 points.)

A. 80
B. 88.75
C. 90
D. 85.25

Answer 1

Jenny needs to score 95 on her final exam in order to achieve an average (mean) grade of 80 for her biology class.

Step-by-step explanation:

In order to determine what score Jenny needs on her final exam to attain a mean grade of 80 in her biology class, we must first calculate the total points she has so far. Adding her five exam scores (67, 72, 84, 80, and 82), we get a total of 385 points. Since she has taken five exams, and she needs an average (mean) of 80 after six exams, the total points needed after all exams is 6 exams × 80 points/exam = 480 points. Thus, the score Jenny needs on her final exam is 480 total desired points - 385 current points = 95 points.

Jenny would need to score 95 on her final exam to achieve the required mean score of 80 for the course. Since each exam has a maximum of 100 points, this is a possible score.