By adding all your grades together and dividing it by the number of grades
ex) 100
96
100
the total is 296 and you divide that by 3 because 3 is the number of grades you have. Therefore your grade average is 98.6 which sums um to 99
ex) 100
96
100
the total is 296 and you divide that by 3 because 3 is the number of grades you have. Therefore your grade average is 98.6 which sums um to 99