About this proportion calculator
A proportion says two ratios are equal. To find the missing value, cross-multiply: in 3/4 = 12/x, 3x = 48, so x = 16. It is the arithmetic behind scaling recipes, map distances and unit prices.
A:B
Proportion Calculator
Details
How to use Proportion Calculator
What the tool does, how to run it, and what to expect from the result.
At a glance
Who Proportion Calculator is for
A quick way to understand who this helps, what it solves, and where it connects next.
Best fit
Students, teachers and anyone checking a calculation.
Ideal for
Using the proportion calculator without installing anything or signing up.
FAQ
Common questions
Short answers for the questions people usually have before trying a utility like this.
How do you solve a proportion?
Multiply diagonally and divide: for A/B = C/x, x = B × C ÷ A.
What is a real example?
A recipe for 3 people uses 4 eggs; for 12 people you need 4 × 12 ÷ 3 = 16 eggs.
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