How to use this calculator
Choose a mode and enter the ratio parts. Scaling and proportion both solve for the second term of the equivalent ratio.
Formula and method
a:b = c:x gives x = bc/a; a simplified integer ratio divides both terms by their greatest common factor.
Worked example
6:9 simplifies to 2:3; with c=12 the missing term is 18.
Assumptions and supported scope
Nonnegative integer parts for simplification; real nonnegative c for scaling. The original first term must be positive to solve from c.
Method references
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