Rule of Three Calculator: Solve Direct Proportions
Calculate the direct rule of three: If A corresponds to B, what does C correspond to? Get the result in seconds.
Result (X)
10,00
X = (20 × 50) / 100 = 10,00
Direct: X = (B×C)/A. Inverse: X = (A×B)/C (more workers, fewer days).
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Frequently asked questions
How do you calculate the rule of three?
For a direct rule of three, multiply the cross values and divide by the remaining number. For example, if A equals B and C is known, then D = (B × C) / A.
What is the direct rule of three used for?
It is used to solve proportional problems in everyday life, such as calculating prices, quantities, percentages, or converting units when two values are directly related.
What is the Rule of Three?
The rule of three is a mathematical method to find an unknown value when three other values are known, based on proportional relationships. It is especially useful in daily situations like shopping, cooking, and financial planning, where quantities increase or decrease in proportion.
How to Use the Rule of Three Calculator
Enter the values for A, B, and C in the calculator. The tool automatically applies the direct proportion formula to compute the missing value D. The result appears instantly, saving you time and avoiding manual errors. Try it now for accurate calculations.