- Fill in all the boxes with the appropriate numbers (For example – 1st and 2nd Quarter are each 42.5% of your semester grade. The Final Exam is 15% of your semester grade).
- Leave either the semester grade or the final exam grade box blank, depending on which one you want to calculate
- Press the appropriate button, depending on what you are trying to calculate
How to Calculate Weighted Grades
It’s nice to have a grade calculator and just plug in the information; however, for some of you, you want to know how the math works. How exactly is this program calculating grades? You’re curious to know the math behind the magic. This is understandable. Let’s satisfy that curiosity by looking at the different ways we calculate grades.
Determining your current course grade
- To determine your grade in a course, we must start by exploring how grades are weighted in a course. If we have a course that is weighted 20% for quizzes, 35% for tests, and 45% for a final exam, then we first need to turn the percentages into decimals:
20%= .2 (Quizzes)
35%= .35 (Tests)
45%= .45 (Final Exam)
When the decimals are added together, they should equal 1.
.2 + .35 + .45=1
This indicates that 100% of the grade (20% + 35% + 45%=100%) is represented.
- Once we have renamed the percentages as decimals, the math is a little easier. We now take each weight and multiply it by the grade for each category:
weight of a category (as a decimal) X grade in that same category
Let’s pretend our quiz average is an 85, our test average is a 72, and our final exam score is an 83:
Quizzes: .2 X 85 = 17
Tests: .35 X 72 = 25.2
Final Exam: .45 X 83 = 37.35
- Next we add these weighted totals together:
17 + 25.2 + 37.35 = 79.55
- This final sum is the course grade.