The formula
Needed = (Target − Current × (1 − Weight)) ÷ Weight
Example: with an 85% now and a final worth 20%, reaching a 90% needs (90 − 85 × 0.8) ÷ 0.2 = 110%. That's out of reach without extra credit, but an 80% overall only needs a 60% on the final.
Common letter grade cutoffs
| Letter | Percent |
|---|---|
| A | 90% and up |
| B | 80% – 89% |
| C | 70% – 79% |
| D | 60% – 69% |
| F | Below 60% |
Some schools use plus and minus grades or different cutoffs, so check your syllabus.
Frequently asked questions
What if my class uses points instead of percentages?
Divide your points earned so far by the points possible to get your current percentage, and divide the final's points by the course total to get its weight.
What if the answer is over 100%?
Then the target isn't possible on the final alone. Ask your teacher about extra credit, or aim for the next grade down.