20% grades: 100, 99, 100, 100, 100, 100 Find the average of your 20% grades= = 99.833333 80% grades: 39, 100 Find the average of your 80% grades = = 69.5 Grade average for class = .20(20% average) + .80(80% average) Grade average for class = .20(99.833333) + .80(69.5) = 75.166667. Edwin