A weighted grading system is one in which the different types of assessments that make up the final grade are grouped together. For example, a course may consist of homework, quizzes, and exams. In a weighted grading system, all homework assignments might be worth 20% of the final grade, while quizzes may be worth 30%, and exams 50%. Thus, the final grade is calculated by determining the average score achieved in each type of assessment and multiplying by their respective weight in the course. The final grade is the sum of the products of the average scores and their respective weights. For example, the final grade of a student who has an average homework score of 98%, quiz score of 88%, and exam score of 83% is calculated as follows:

(98)(0.2) + 88(0.3) + 83(0.5) = 87.5

This grading system is in contrast to a point-based system in which each assignment is worth a given number of points, and the final grade is calculated by dividing the sum of the scores of every assignment by the total number of possible points. For example, a course may consist of 20 homework assignments worth 10 points each, 5 quizzes worth 50 points each, and 3 exams worth 100 points each. The total number of possible points is:

20(10) + 5(50) + 3(100) = 750

Thus, a student who obtained 187 points for homework, 201 points on their quizzes, and 238 points on their exams would have a final grade of,

 187 + 201 + 238 750
=
 626 750
= 0.835

or an 83.5%, which corresponds to a letter grade of B in most grading systems. Note that even in a point-based grading system, it is possible to determine the weight of each assessment with respect to the final grade. To do so, simply calculate the percentage of each type of assessment by dividing the total number of possible points for each assessment by the total number of possible points for all assessments. Using the same example above, it is possible to score 200 points on homework, 250 for quizzes, and 300 for exams. Thus, the weight of each can be calculated as follows:

Homework:
 200 750
= 26.67%
Quizzes:
 250 750
= 33.33%
Exams:
 300 750
= 40%

## The importance of the final

The final exam is an important aspect of the final grade. In many courses, the final exam is worth a significant portion of the grade, usually ranging from 30-50%. For this reason, even if a student has done well on all other assessments in the course, the final exam can often bump a student's grade up or down to the next letter grade. For example, a student with a B+ in a course may be able to achieve an A- depending on how well they do on the final. Similarly, if they do poorly on the exam, they may instead obtain a B.

The final grade calculator is useful for determining how high a student needs to score to achieve the next highest letter grade, or how poorly they can perform on an exam to maintain a desired grade. The calculation is also relatively simple since the student should already know the result of all their other grades – they only need to know the weight of the final to find out what they need to score to achieve their desired grade using the following formula:

(1 - w)c + wf = d

f =
 d - (1 - w)c w
 Where f = final exam score d = desired final grade w = weight of the final exam c = current grade (excluding final)

In the US grading system, the final grade corresponds to a given point value, which is used to determine a student's grade point average (GPA). GPA is important because it summarizes a student's overall academic performance with a single value. GPA scales vary by institution. The following table depicts the relationship between letter grades, percentage grades, and grade point values in a commonly used GPA scale:

A+97-1004.3 (or 4.0)
A93-964.0
A-90-923.7
B+87-893.3
B83-863.0
B-80-822.7
C+77-792.3
C73-762.0
C-70-721.7
D+67-691.3
D63-661.0
D-60-620.7
FBelow 600.0

Note that a grade point value is a different value from the point value referenced in a point-based grading system.