Description
Calculate variable=quantity*unitCost and total=variable+fixedFee.
A ratio compares quantities under a stated numerator and denominator. Fractions, percentage numerals, and percentage-point changes use different conventions, and changing a part can also change its whole. Unit consistency, zero denominators, rounding, and the order of adjustments determine the result.
Calculate variable=quantity*unitCost and total=variable+fixedFee.
When to use this tool
Use Proportional Cost Fixedfee Base when you need this specific ratio, allocation, transformation, interval, or adjustment-order calculation with an explicit base.
How to use the tool and how it works
- Enter quantity, unitCost, fixedFee. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read variable, total. Use the output convention below.
Calculate variable=quantity*unitCost and total=variable+fixedFee. Require nonnegative quantity and unit cost while allowing a signed fixed fee.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| quantity | Quantity | Required. Finite number; minimum 0. |
| unitCost | Unit Cost | Required. Finite number; minimum 0. |
| fixedFee | Signed fixed amount; negative values act as a credit. | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| variable | Variable | Required. Finite number. |
| total | Total | Required. Finite number. |
{
"input": {
"quantity": 5,
"unitCost": 12,
"fixedFee": 8
},
"output": {
"variable": 60,
"total": 68
}
}Limitations and assumptions
- A negative fixed fee is an explicit credit and total may be negative. The tool does not determine billing terms, taxes, currency rounding, market prices, or a payment obligation.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Signed zero is exported as zero.
Alternative or Complementary methods
Check numerator, denominator, units, and adjustment order before comparing results. Use a complete allocation or physical mixture model when a single arithmetic term leaves relevant constraints unspecified.
References
Similar or alternative tools
- Proportional Cap Boundary Mass
Return uncapped=total*fraction, capped=min(uncapped,cap), and boundaryExcess=max(0,uncapped-cap).
- Proportional Margin One Input Sensitivity
Differentiate proportional gross margin (revenue-cost)/revenue with respect to both inputs.