What do I need on my final to get a C?
With a 68% going in and a final worth 25%, you need 76.00% on the final to finish at 70% (a C). Full table for every current grade and final weight.
Formula: (target − current × (1 − weight)) ÷ weight. Assumes the final is the only remaining grade.
| Current grade | Final 10% | Final 15% | Final 20% | Final 25% | Final 30% | Final 35% | Final 40% | Final 50% |
|---|---|---|---|---|---|---|---|---|
| 50% | 250.00% | 183.34% | 150.00% | 130.00% | 116.67% | 107.15% | 100.00% | 90.00% |
| 55% | 205.00% | 155.00% | 130.00% | 115.00% | 105.00% | 97.86% | 92.50% | 85.00% |
| 60% | 160.00% | 126.67% | 110.00% | 100.00% | 93.34% | 88.58% | 85.00% | 80.00% |
| 65% | 115.00% | 98.34% | 90.00% | 85.00% | 81.67% | 79.29% | 77.50% | 75.00% |
| 70% | 70.00% | 70.00% | 70.00% | 70.00% | 70.00% | 70.00% | 70.00% | 70.00% |
| 75% | 25.00% | 41.67% | 50.00% | 55.00% | 58.34% | 60.72% | 62.50% | 65.00% |
| 80% | 0% | 13.34% | 30.00% | 40.00% | 46.67% | 51.43% | 55.00% | 60.00% |
| 85% | 0% | 0% | 10.00% | 25.00% | 35.00% | 42.15% | 47.50% | 55.00% |
| 90% | 0% | 0% | 0% | 10.00% | 23.34% | 32.86% | 40.00% | 50.00% |
| 95% | 0% | 0% | 0% | 0% | 11.67% | 23.58% | 32.50% | 45.00% |
| 100% | 0% | 0% | 0% | 0% | 0% | 14.29% | 25.00% | 40.00% |
above 100% (not reachable without extra credit) · 90% or higher · already secured
How to read this table
Find your current grade in the left column, the one that includes everything except the final. Move across to the column for your final’s weight from the syllabus. The cell is the lowest final exam score that gets you to 70%. Scores are rounded up to two decimals, so hitting the number exactly reaches the target.
Three things that change the answer
- Your current grade must exclude the final. If your gradebook already counts the final as a zero, your real “grade before the final” is higher than it shows.
- The final’s weight must be its own category. If the final sits inside an “Exams 50%” category with other tests, its real weight is smaller than 50% and this table overstates what you need.
- Rounding is the instructor’s decision. 69.5% may or may not round up to 70%. The table assumes it does not.
When the number is over 100%
The target is gone under normal rules. Pick the next grade down and plan for that instead; chasing an impossible number costs effort that could secure the grade below it. Confirmed extra credit on the final is the only exception.