Suppose that the class grade for a six-week period is based on three tests , each of which counts for 15%, four quizzes , each of which counts for 10%, and a homework notebook (HW), which counts for 15%. The grades are recorded in a spreadsheet similar to the one below.

Which of the following formulae would NOT be a correct calculation of the six-week weighted average for Jatin?

Correct option is D

The correct calculation of Jatin’s six-week weighted average involves multiplying the test scores and quiz scores by their respective weights and summing them up. Formula (d) divides the test scores by 15 instead of multiplying them by 0.15, which is incorrect. The correct approach requires multiplying each component by its respective weight (i.e., 0.15 for tests and 0.1 for quizzes).
Information Booster:
1. The three tests each account for 15% of the grade, and the four quizzes account for 10% each.
2. The homework (HW) contributes 15% to the overall grade.
Additional Knowledge:
· Formulae that perform simple division without considering the actual weight of each component will result in incorrect values.
· Spreadsheet software like Excel or Google Sheets allows the use of formulae to calculate weighted averages easily.