Calculator form
Example data table
Example inverse proportion data using the constant k = 120.
| x | y | x × y |
|---|---|---|
| 3 | 40 | 120 |
| 4 | 30 | 120 |
| 5 | 24 | 120 |
| 6 | 20 | 120 |
| 8 | 15 | 120 |
| 10 | 12 | 120 |
Formula used
Inverse proportion rule: x × y = k
Main equation: y = k / x
Find the constant: k = x × y
Find a missing second x: x2 = (x1 × y1) / y2
Find a missing second y: y2 = (x1 × y1) / x2
Interpretation: when one variable increases, the other decreases so their product stays constant.
How to use this calculator
- Select the calculation mode that matches your problem.
- Enter the known values in the visible input fields.
- Leave the required unknown field blank when solving a missing value.
- Click Submit to display the result above the form.
- Review the steps, graph, and generated comparison table.
- Use the export buttons to save the current result as CSV or PDF.
FAQs
1. What is an inverse proportion?
An inverse proportion means one value decreases when the other increases, while their product remains constant. It is commonly written as y = k / x.
2. How do I know whether values are inversely proportional?
Multiply each x value by its matching y value. If the product stays the same for all valid pairs, the relationship is inverse.
3. Why are zero values restricted here?
Inverse proportion uses division, so x cannot be zero in y = k / x. Zero would make the relationship undefined and break the calculation.
4. What does the constant k represent?
The constant k is the fixed product of x and y. It defines the full inverse curve and keeps every valid pair linked to the same relationship.
5. Can this calculator solve a missing value from two pairs?
Yes. Enter the first complete pair, then provide either x2 or y2. The calculator uses the constant product to solve the missing second value.
6. What does the graph show?
The graph plots the inverse curve for your constant. It also marks the submitted or solved points so you can visually inspect the relationship.
7. What is the purpose of the generated table?
The generated table helps compare several x values against their matching y values. It also confirms that x × y remains equal to the same constant.
8. When should I export CSV or PDF?
Use CSV when you want spreadsheet-ready data. Use PDF when you need a shareable report containing the summary, steps, and current comparison table.