Proportion Calculator
MathSolve a proportion A/B = C/D for the missing numerator C, given A, B, and D.
C
The missing value that keeps A/B equivalent to C/D, found by cross multiplication.
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Creators
Odeh Ahwal0people find this calculator helpful
Views
Helpful
Saved
Embeds
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Frequently Asked Questions
What is cross multiplication?
Cross multiplication solves a proportion A/B = C/D by multiplying the numerator of one side by the denominator of the other: A*D = B*C. Rearranging gives C = (A*D)/B.
How is this different from the ratio calculator?
The ratio calculator is the more comprehensive version, solving A:B=C:D for D and also showing the simplified form of A:B. This calculator is a narrower, single-purpose tool solving for a different position in the proportion, C given A, B, and D.
What is a real example of this?
Scaling the fraction 7/12 up to have a denominator of 96: solving 7/12 = C/96 with cross multiplication gives C = (7 x 96)/12 = 56, so 7/12 is equivalent to 56/96.
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