Question

Imagine the following scenario: A student is about to take the final exam and has completed all assignments except the final exam. Out of 100 possible Project Assignment points, they have received 61 points. Out of 100 possible Quiz points, they have received 54 points If the student wanted to receive an overall B grade in the class, what do they need to score on the final exam? Give your answer as a percentage rounded to the nearest for decimal place (no percentage sign necessary), e.g., if I calculated 99.68%. I would enter 99.7.

Project Assignments: 60%
quizzes: 10%
final exam:30%​

Answer 1

126.7 if B=80

93.3 if B=70

Explanation:

Let F represent the student's score on the final exam, and let B represent the percentage required for a grade of B. Then we must have ...

0.60(61) +0.10(54) +0.30F = B

B = 0.30F +42

F = (B -42)/0.3

__

If a grade of B requires 80 points or more, then the required grade on the final is ...

F = (80 -42)/0.3 = 38/0.3 = 126 2/3

The student must get 126.7% on their final to achieve an overall average of 80.

__

If a grade of B requires 70 points or more, then the required grade on the final is ...

F = (70 -42)/0.3 = 28/0.3 = 93 1/3

The student must get 93.3% on their final to achieve an overall average of 70.