The Rule of Three is a mathematical technique used to find an unknown value based on known proportions. At Scalar, you can solve everything from quick market calculations to complex engineering problems involving multiple variables.
How to use this tool?
- Choose between Simple mode (two quantities) or Compound mode (three or more quantities).
- Define if the relationship is Direct (when one increases, the other also increases) or Inverse (when one increases, the other decreases).
- Enter the known values, and Scalar will calculate the value of X instantly.
View Theory and Difference between Direct and Inverse
Simple Rule of Three
Used when dealing with two quantities.
- Direct: If 2 builders construct 4 meters of a wall, 4 builders will construct 8 meters. (As builders increase, the wall length increases).
- Inverse: If 2 builders take 10 days, 4 builders will take 5 days. (As builders increase, the time decreases).
Compound Rule of Three
Used for three or more quantities. The secret is to compare each quantity with the one containing X, determining whether each individual relationship is direct or inverse before setting up the final equation.