Today you will
- make red error codes and fix them
- check that your budget totals make sense
- log what you checked
No budget file? Make {{code:05_project_budget}} in {{code:05_budget}} now. Put these headings in row 1 and five of your own costs in rows 2 to 6. Then put {{formula:=SUM(C2:C6)}} in {{cell:C7}}.
Item | Category | Cost | Notes
Warm-up
A till says €400 for one coffee. What would you check first, the numbers typed in or the sum?
A red error code means the spreadsheet cannot finish a sum.
- #DIV/0! means you divided by zero or an empty cell.
- #VALUE! means there is a word where a number should be.
- #REF! means the formula points at a cell you deleted.
- #NAME? means a function name is spelled wrong.
To fix one, click the red cell and read the formula bar. A sanity check asks whether the number makes sense for real costs.
Example
Typing {{formula:=SUMM(D2:D5)}} instead of {{formula:=SUM(D2:D5)}} gives #NAME?.
You will break some formulas and then fix them on a practice tab called {{code:Error_Lab}}. Follow the steps in the box below. You will need these headings and this stock list.
| Item | Cost (€) | Quantity | Line total (€) | Cost per unit (€) |
|---|---|---|---|---|
| Coffee beans (1 kg) | 12.00 | 0 | ||
| Paper cups | 9.50 | three | ||
| Napkins | 4.00 | 10 | ||
| Oat milk | 3.20 | 6 |
Common snags
- #DIV/0! is still there: click it and check the formula bar for a cell that is blank or 0.
- #NAME? is still there: clear the cell and type the formula again, starting with =.
- The total looks far too big or too small: click it and check that the range only covers your costs.
Independent Practice
- Open the main budget tab in {{code:05_project_budget}}, not {{code:Error_Lab}}.
- Click each formula cell and fix any red error codes.
- Change your biggest cost by €1 and check that the total changes. Then put the real figure back.
- Tell a partner roughly what your total should be.
- Two rows under your last row, type the log below: one row per fix, or one row saying none.
Sanity-check log
Date | Cell/range | Issue | Fix
- My budget has no red error codes.
- My total changed when I changed a cost, and it looks right.
- My Sanity-check log is under my data.
- The file is still {{code:05_project_budget}} in {{code:05_budget}}.
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