Inverse Proportion Calculator
Find a fourth value when one quantity rises as the other falls proportionally. Processing takes place locally in your browser.
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What this tool actually does
Solves an inverse proportion a times b = c times x with x = a times b divided by c and shows the substituted formula and rounded result.
Checkable behavior
All three values must be finite and greater than zero. Decimal precision must be a whole number from 0 through 12.
Controls, output and limitations
Verified example: 4 workers taking 6 days gives 8 workers taking x = 4 times 6 divided by 8 = 3 days under perfect inverse scaling.
The calculation assumes a constant product. Real work can have coordination overhead, minimum durations, capacity limits or tasks that cannot be divided.
The result is a mathematical estimate using browser floating point. Check assumptions and domain rules before staffing, dosing, engineering or financial decisions.
Output uses a decimal point; very large results may use scientific notation. Floating-point rounding can display a very small positive result as zero. Results beyond the numeric range are rejected. Changing inputs, errors and clear reset the x preview to “?”; calculate again to update it.
Processing takes place locally in your browser.