Solve proportions: if A is to B as C is to D, find the missing value D.
Solve proportions: if A is to B as C is to D, find the missing value D.
A/B = C/D → D = B×C/A
3/4 = 9/? → ? = 12.
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What is Proportion Solver Calculator?
Solve proportions: if A is to B as C is to D, find the missing value D.
What formula does this use?
This calculator uses: A/B = C/D → D = B×C/A
Is this calculator free?
Yes! All calculators on CalcNest AI are 100% free with no account required.
Is my data safe?
Absolutely. All calculations run locally in your browser. We never store or transmit your input data.