Calculators
Proportion Calculator
Find X from three known numbers
Enter the values and the result will appear here.
Formula
A relates to B the same way C relates to X.
A finished calculation is added to the history automatically.
History
Entries: 0Nothing yet — finished calculations will appear here by themselves.
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Частые вопросы
How do I solve a proportion?
In A : B = C : X the product of the extremes equals the product of the means: A·X = B·C, so X = C·B / A. Enter A, B and C and X is calculated for you.
What if A is zero?
You cannot divide by zero, so the A field rejects it and X is not calculated.
Does it work for the rule of three?
Yes, the rule of three is the same proportion. If 2 kg cost 3 roubles, how much do 4.5 kg cost? A = 2, B = 3, C = 4.5 gives X = 6.75.
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