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Mathematics

Proportion Calculator

Solve for the missing value in a proportion a/b = c/x

Proportion Calculator (Solve for x)

Given a/b = c/x — enter a, b, c to solve for x.

a
b
c

A proportion is an equation stating two ratios are equal: a/b = c/d. Cross-multiplication (a×d = b×c) lets you solve for any missing value. Proportions are used in scaling, cooking, maps, and unit conversion.

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Tip: Always label your units when setting up proportions — it prevents inverting the ratio by accident.

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