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Rule of Three

Solve direct and inverse proportion problems for the missing value.

Runs entirely in your browser. Nothing you enter leaves your device.

Proportion

A is to B as C is to X

Result

is X

How to use

  1. Fill in the form fields with your values.
  2. The result appears below the form as soon as the input is valid.
  3. Use Copy or Download to save the result, or Reset to clear the form.

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