About this exercise
A co-teacher's average formula gives excused students low grades. Give a fixed formula for I2 (filled down) in one code block that skips EX marks and blank cells instead of counting them as zeros, shows the text No grades when a student has no scores yet, and rounds to 1 decimal. Then write exactly 1 numbered line starting Problem: under 20 words. Under 35 words outside the code.
Common mistakes when you ask AI for this
- Accepting a quick patch. The AI may wrap it in IFERROR and keep dividing by 6. Try: Add: "Skip EX and blanks instead of counting them as zeros."
- Forgetting new students. A student with no scores shows an error or 0. Try: Add: "Show No grades when there are no scores yet."
- Leaving rounding out. Parents see averages like 84.333333. Try: Add: "Round to 1 decimal."
- Not limiting the reason. The AI writes paragraphs about SUM versus AVERAGE. Try: Add: "Then exactly 1 numbered line starting Problem:, under 20 words."
- Getting a menu of options. The AI likes to offer two or three versions of the formula, so you're left to pick and test them yourself. Try: Add: "Give one formula only, in one code block, no alternatives."
What a strong prompt includes
- Skips EX and blanks
- Handles new students
- Asks for rounding
- Asks for one reason line
- Asks for one answer only
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