How many points are there total? (3*100)+250 = 550
So far, he has 72 + 85 + 78, or 235
He needs 0.80 * 550 for a B, or 440 points
440 - 235 = 205 points on the final to get a B
Percentage-wise, he needs 205/250, or 0.82
7.8m questions
10.5m answers