How it works
Total contribution before discount is compared with the lower unit contribution after discount. This form solves for original quantity; enter the known quantities in Required discounted quantity, Original unit price (same currency), Unit variable cost (same currency), Price discount.
Inputs and units
| Input | Example value | What to enter |
|---|---|---|
| Required discounted quantity | 150 | Formula symbol: newq. Enter a numeric value. Must be greater than zero. |
| Original unit price (same currency) | 100 | Formula symbol: price. Enter a numeric value. Must be greater than zero. |
| Unit variable cost (same currency) | 40 | Formula symbol: cost. Enter a numeric value. Use a non-negative value. |
| Price discount | 20 % | Formula symbol: discount. Enter the percentage as a number: for 15%, enter 15. Use a non-negative value. Allowed range: 0–99.999. |
Worked example
Show example inputs and results
This example is generated by the same calculation engine using the starting values in the form. Your own inputs produce your own result.
- Required discounted quantity
- 150
- Original unit price (same currency)
- 100
- Unit variable cost (same currency)
- 40
- Price discount
- 20 %
Complete example results
- Original quantity
- 100
Reading the result
The result solves for original quantity from the entered quantities. Check the result unit and the formula conditions before using it.
Questions and answers
Can I use the example values for my own calculation?
The example values illustrate the calculation. Replace every input with your own information, especially dates, rates and the selected operation.
When can I use the original quantity result?
Unit variable cost is fixed and post-discount contribution must be positive. Quantity is continuous sales volume; an increase in demand is not promised. All monetary inputs must use the same currency; currency conversion, tax and automatic fees are excluded. The source defines unit and total contribution; required volume is derived algebraically by equating contribution before and after discount.
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
Are my inputs sent to a server?
The calculator processes inputs in your browser. Its code does not send your values to a server.
Method sources: openstax.org