Joint and combined variation worksheet
Joint variation multiplies: z = kxy. Combined variation mixes direct and inverse: z = kx over y. Either way the method is the same as direct variation, use the first set of values to find k, then use k with the second set.
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Pick more than one for a sheet that mixes them.
Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep
Sigma Prep · sigmaprep.io/worksheets Name Joint and Combined VariationDate Period Answer each question.
Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep |
Sigma Prep · sigmaprep.io/worksheets Name Joint and Combined VariationAnswer keyVersion 1Date Period Answer each question.
Free math worksheets at sigmaprep.io/worksheets© 2026 Sigma Prep |
How to do these
varies jointly with and , and when , . Find when and
- z = kxy, so 24 = 6k and k = 4.
- z = 4 times 4 times 5.
The answer is .
Where students go wrong
Adding where the variation multiplies. "Varies jointly with x and y" is kxy, never k(x + y).
Also called joint variation, combined variation, direct and inverse variation or constant of variation.
What you can put on this worksheet
- Direct variation
- If varies directly with and when , find when →
- Inverse variation
- If varies inversely with and when , find when →
- Joint variation
- varies jointly with and , and when , . Find when and →
- Combined variation
- varies directly with and inversely with , and when , . Find when and →
- Direct, inverse or neither
- Direct variation, inverse variation, or neither: → Inverse variation,