text: How many units for the respective classes? If they're all the same, then your divisor is 6, 1 for each class. GPA is a TLA meaning Grade Point Average. A = 4, B = 3, C = 2, D = 1, and F = 0. So you add up all the numeric substitutions and divide by the number of samples. In this instance, the answer is (3 + 3 + 3 + 3 + 4 + 2)/6 = 3.0.