Rule of Three Calculator
Solve a direct proportion a : b = c : x.
Solve a direct proportion
x
—Formula
For a ÷ b = c ÷ x, x = (b × c) ÷ a. a must not be zero. This tool handles direct proportion only.
Worked example
a=2, b=10, c=5 gives x=25.
Solve a direct proportion a : b = c : x.
x
—For a ÷ b = c ÷ x, x = (b × c) ÷ a. a must not be zero. This tool handles direct proportion only.
a=2, b=10, c=5 gives x=25.