THE NUMBERS, EXPLAINED
How to use this calculator.
One worker cleans size groups in entered order. Times must include access equipment handling for each window; setup is once per visit. Does not assess work-at-height safety.
Start with your inputs
Enter windows in each size group, measured minutes per window by group, setup and packing time (min). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Windows in each size group | 4,2 |
| Measured minutes per window by group | 5,10 |
| Setup and packing time (min) | 20 |
A worked example
With the example inputs above, group work times (min) is 20, 20. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Group work times (min) | 20, 20 |
| Total equipment booking time (min) | 60 |
How this is calculated
Group work times (min)
Multiply window count by measured handling time for each group.
Total equipment booking time (min)
Add group work times and one setup/packing allowance.
Symbols and units
- a
- Windows in each size group
- b
- Measured minutes per window by group
- c
- Setup and packing time (min)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
One worker cleans size groups in entered order. Times must include access equipment handling for each window; setup is once per visit. Does not assess work-at-height safety.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Group work times (min); Total equipment booking time (min). The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: One worker cleans size groups in entered order. Times must include access equipment handling for each window; setup is once per visit. Does not assess work-at-height safety.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
OpenStax: Solve proportions and their applications ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
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