Chapter 6.A, Problem 44E

Weighted Means. We often deal with weighted means, in which different data values carry different weights in the calculation of the mean. For example, if the final exam counts for 50% of your final grade and 2 midterms each count for 25% then you must assign weights of 50% and 25% to the final and midterms, respectively, before computing the mean score for the term. Apply the idea of weighted means in the following exercises.

44. Class Grade. Ryan is taking an advanced psychology class in which the midterm and final exams are worth 35% each and homework is worth 30% of the final grade. On a 100-point scale, his midterm exam score was 85.5, his homework average score was 94.1, and his final exam score was 88.5.

a. On a 100-point scale, what is Ryan’s overall average for the class?

b. Ryan was hoping to get an A in the class, which requires an overall score of 93.5 or higher. Could he have scored high enough on the final exam to get an A in the class?