For purposes of computing grade point averages, a scale shall be used as follows: A = 4; B = 3; C = 2; D = 1; and F = 0 grade points. A campus may use “plus” and “minus” designations in combination with letter grades and may compute grade point averages taking plus and minus values into account. In said computations a plus shall be computed by adding .3 to the value assigned to the letter grade with which it is combined and a minus shall be computed by subtracting .3 from the value assigned to the letter grade with which it is combined except that no grade point value shall be less than 0 or greater than 4.0. In the case of grading experiments approved by the chancellor, finer decimal values may be assigned.