My final is worth 25% — what score do I need?
With a quarter of the grade left, your ceiling is your current grade plus a quarter of the distance to 100. From 80% that ceiling is 85, so the B+ at 87 is not available at any exam score. What is available is a B, and it needs a 92 on the paper.
Common plus/minus convention; many schools use straight letters or different cut points.
You need 108% on the final.
That is above 100%, so 87% is out of reach from the final alone. The highest you can finish with is 85%.
🔢 Show the math
- Work graded so far covers 75% of the course; 25% is still to come.
- Points already banked: 80% × 75% = 60 points of the 100 available.
- To finish at 87% you still need 27 points from the remaining 25%.
- 27 ÷ 25 × 100 = 108% on what is left.
- That is above 100%, so this target is out of reach from the remaining work alone — the best you can still finish with is 85%.
What you need, at every current grade
With a final worth 25% of your course grade and a B+ (87%) as the goal, this is the score you need on the final from each starting point:
| Current grade | You need on the final | Reachable? |
|---|---|---|
| 92% | 72.0% | Yes |
| 88% | 84.0% | Yes |
| 84% | 96.0% | Yes |
| 80% | 108.0% | Not with this final alone |
| 74% | 126.0% | Not with this final alone |
| 68% | 144.0% | Not with this final alone |
Grading scales vary by institution — your school's own table and syllabus govern. Conversions shown here follow common published conventions.
Frequently asked questions
How do I work out my own ceiling at this weight?
Take the distance between your current grade and 100, keep a quarter of it, and add that back. From 80 the distance is 20, a quarter is 5, and the ceiling is 85. The same shortcut gives your floor: from 80, dropping the whole quarter leaves 60.
The required score came back above 100 — what now?
Reset the target to something the arithmetic allows and study for that with real margin. Here the B at 83 needs a 92 and the B-minus at 80 needs an 80 flat. Both are ordinary asks; the B+ is not an ask at all, and hours spent on it come out of the grade you can still hold.
Is a quarter-weight final worth serious preparation?
Yes, and the reason is defensive as much as offensive. Twenty-five points of your grade are unwritten, so the same weight that limits your climb to five points would let a poor result cost you twenty. Most students only picture the upside of a heavy exam and never price the other end.
Would extra credit rescue the B+ here?
Only a large amount of it, and it is the one lever that still moves the ceiling. Each point added to your current grade lifts the maximum possible finish by three quarters of a point, so 87 stays out of reach until your current grade passes 82.7 — and even then it would take a perfect paper.
Other targets
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