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Calculators
Rule of Three Calculator
Solve a simple rule of three online. Enter three values and automatically calculate the fourth.
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How does the rule of three work?
The simple rule of three solves proportions of the type A:B = C:X, where X = (B × C) / A. It is used to calculate proportional prices, speeds, mixtures, recipes and any directly proportional quantity.
Example: If 2 kg cost R$ 4, how much do 6 kg cost? X = (4 × 6) / 2 = 12.
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