Proportion Calculator
Calculate the missing value X in a proportion
Formula: A : B = C : X → X = (B × C) ÷ A
A:B=C:X
Proportion Calculator Online
Our proportion calculator solves equations in the form A/B = C/X. Enter three known values and the calculator finds the fourth. Proportions are used in many areas: maths, cooking, photography, construction and design. Formula: X = (B × C) / A