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Inverse Variation Calculator.
For y = k/x, derive k and calculate y at a new x.
Set your values
Results update as you type.
Results update automatically as you type.
Use Cases
Physics: Inverse Square Law
Use inverse variation to model relationships like gravitational force or light intensity, which decrease with the square of distance.
Example: If force is 10 N at distance 2 m, find force at distance 4 m.
Work and Time Problems
Inverse variation applies when the number of workers and time to complete a job are inversely proportional.
Example: If 5 workers take 8 hours, how long for 10 workers?
Frequently Asked Questions
- What is inverse variation?
- Inverse variation describes a relationship where one variable increases as the other decreases, following the equation y = k/x, where k is the constant of variation. This calculator helps you find k and then compute target y values.
- How do I use this calculator?
- Enter the known x and y values to calculate the constant k. Then, enter a target x value to find the corresponding y value. The calculator will display the constant and the target y.
- What if I need to find x for a given y?
- This calculator is designed to find y for a target x. If you need to find x, you can rearrange the formula to x = k/y, but this calculator does not directly compute that.
Tips & Common Mistakes
Tips
- Ensure the known x and y values are positive and non-zero, as division by zero is undefined.
- Double-check that the target x is also non-zero to avoid errors.
- Use the constant k to verify your results: y * x should equal k for any pair.
- This calculator assumes a simple inverse relationship, not inverse square or other powers.
Common Mistakes to Avoid
- Entering zero for x or y, which leads to division by zero or an undefined constant.
- Confusing inverse variation with direct variation, where y = kx instead of y = k/x.
- Forgetting to use the same units for x and y as in the original problem.
Last updated: August 13, 2026