Rule of Three Calculator

Solve direct and inverse proportions easily.

Value A

Value B

Value C

Value X (Result)

How it works

1020

30x

x = (20 × 30) / 10

The **Rule of Three** is a method of having three numbers to help find the fourth.

Direct Rule of Three: Used when the relationship between the quantities is direct (if one increases, the other increases).
Inverse Rule of Three: Used when the relationship is inverse (if one increases, the other decreases).

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Tutorial

Solve direct and inverse proportions easily.

Use Cases

"Rule of Three Calculator"

Calculate the factorial of a non-negative integer.

Generate a sequence of Fibonacci numbers up to a specified term.

Perform addition, subtraction, multiplication, and division of fractions.

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