Multiply each category score by its weight, sum all products, then divide by total weight. For example: Homework 92% x 20% + Midterm 78% x 30% + Final 88% x 50% = (18.4 + 23.4 + 44.0) / 100 = 85.8%.
- Step 1: Multiply each score by its weight percentage
- Step 2: Add all weighted scores together
- Step 3: Divide by total weight (should be 100%)
- Example: 92 x 0.20 + 78 x 0.30 + 88 x 0.50 = 85.8
- If weights don't sum to 100%, result is still valid as weighted average
| Category | Score | Weight | Contribution |
|---|---|---|---|
| Homework | 92% | 20% | 18.4 pts |
| Midterm | 78% | 30% | 23.4 pts |
| Final | 88% | 50% | 44.0 pts |
| Total | - | 100% | 85.8% |