Question

Rita earns scores of 88,87,85,89 and 88 on her five chapter tests for a certain class and a grade of 80 on the class project. The overall average for the course is computed as follows: the average of the five chapter tests makes up 30% of the course grade; the project accounts for 50% of the grade; and the final exam accounts for 20% . What scores can Rita earn on the final exam to earn a "B" in the course if the cut-off for a "B" is an overall score greater than or equal to 80 , but less than 90? Assume that 100 is the highest score that can be earned on the final exam and that only whole-number scores are given. To obtain a "B", Rita needs to score between?

Answer 1

To calculate Rita's overall average for the course, we need to consider the weights of each component. The average of the five chapter tests makes up 30% of the course grade, the project accounts for 50%, and the final exam accounts for 20%.

First, you calculate Rita's average score for the five chapter tests. Add up the scores for the five tests (88 + 87 + 85 + 89 + 88) and divide by 5:

(88 + 87 + 85 + 89 + 88) / 5 = 437 / 5 = 87.4

Next, you calculate the contribution of the chapter tests to Rita's overall average. Multiply the average score of the chapter tests by 30%:

87.4 * 0.3 = 26.22

Rita earned a grade of 80 on the project, which accounts for 50% of her overall average.

80 * 0.5 = 40

To calculate the minimum score Rita needs on the final exam, subtract the sum of the chapter test and project scores from 80 (the lowest score needed for a "B" grade):

80 - (26.22 + 40) = 13.78

To earn a "B" grade, Rita needs to score higher than 13.78 on the final exam. However, since only whole-number scores are given, the lowest whole number Rita can score on the final exam is 14.

Therefore, Rita needs to score between 14 and 100 on the final exam to earn a "B" in the course.