Change the scores to percentages by dividing the lower scores by the top attained score. This will give the top score a 100, with the other scores falling lower on the scale. For example, a top score of 75 would then become a 100 and a score of 55 would become a 73 (55 divided by 75), while a 43 would become 57 (43 divided by 75).
Give an A to students scoring in the top 10 percent of the class.
Assign a B to students who score in the next 20 percent.
Mark the next 40 percent of students as Cs. This will be the largest group in the curve.
Give Ds to the next 20 percent of students
Fail only the bottom 10 percent of students in the group by giving them an F.