Convert percentage grades to letter grades:
94 to 100 percent = A
90 to 93 percent = A-
87 to 89 percent = B+
83 to 86 percent = B
80 to 82 percent = B-
77 to 79 percent = C+
73 to 76 percent = C
70 to 72 percent = C-
67 to 69 percent = D+
63 to 66 percent = D
60 to 62 percent = D-
Less than 60 percent = F
Convert the letter grades to grade points. Pass or fail grades labeled with P or N do not translate into grade points and are not commonly included in a quarterly grade-point average:
A = 4.0
A- = 3.7
B+ = 3.3
B = 3.0
B- = 2.7
C+ = 2.3
C = 2.0
C- = 1.7
D+ = 1.3
D = 1.0
D- = 0.7
F = 0.0
Multiply the grade points by the number of credits awarded for each class. For example, if you got a B+ in an introductory sociology class worth 3 credits, multiply the 3.7 grade points for the B+ by 3, the number of credits, to arrive at 11.1 quality points for the class. Repeat this method for other classes.
Add the products obtained by multiplying the grade points by the number of credits per class and divide that sum by the total number of credits attempted for that quarter to obtain the quarterly grade-point average. If the grade points for the quarter total 41.5 and you attempted 12 credits, divide 41.5 by 12 to arrive at a grade-point average of 3.458.