Proportion Calculator
Find the missing value in any proportional equation.
Fill in 3 fields and leave 1 empty so we can find the value (A/B = C/D):
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What is a Proportion?
OneproportionIt is an equality between two ratios. Mathematically, we say that four numbers (A, B, C, and D) form a proportion if the ratio between the first two is equal to the ratio between the last two (A is to B as C is to D).
How our calculator works:
To solve any mathematical proportion problem, you will always have 3 known values and 1 unknown value (the famous \"X\"). All you need to do is fill in the 3 fields that you know and leave the \"X\" field blank.
The tool will automatically apply the cross multiplication rule to isolate the unknown and give you the exact answer right away!