Ratio and Proportion Calculator
Solve one unknown in A:B=C:D or simplify an integer ratio such as 1920:1080.
A : B = C : D
How to use the tool
Enter the requested values and choose a mode or operation when needed. Fields start empty so results always reflect your own data.
For 2:3=8:X, cross multiplication gives 2X=24 and X=12.
Formula and method
This tool solves equal ratios and simplifies them; Rule of Three targets direct or inverse word problems.
A/B = C/D · AD = BC
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