How to use this calculator
Enter a quantity and its matching denominator. For an equivalent or varied rate, enter the new denominator.
Formula and method
Unit rate k=a/b. Direct variation y=kx. Inverse variation k=yx and y=k/x.
Worked example
120 km in 3 h is 40 km/h; at the same rate, 5 h covers 200 km.
Assumptions and supported scope
Inputs are dimensionless numbers; label and check compatible units yourself. Denominators cannot be zero. Inverse variation assumes a constant product.
Method references
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