Calculator
Example Data Table
| Task | Input | Method | Result |
|---|---|---|---|
| Simplify a ratio | 12:18 | Divide by common divisor 6 | 2:3 |
| Solve proportion | 4 / 8 = 9 / x | x = 8 × 9 ÷ 4 | 18 |
| Split a total | 3:2 total 100 | 100 ÷ 5 parts | 60 and 40 |
| Compare ratios | 6:10 and 9:15 | 6 × 15 equals 10 × 9 | Equivalent |
Formula Used
Ratio simplification: A:B becomes A ÷ G:B ÷ G. G is the greatest common divisor after decimal alignment.
Proportion rule: A / B = C / D is true when A × D = B × C.
Missing value: Rearrange the cross products. For A / B = C / x, use x = B × C ÷ A.
Total split: First share = Total × A ÷ (A + B). Second share = Total × B ÷ (A + B).
Percent relationship: Percent = A ÷ B × 100.
How To Use This Calculator
Select the operation that matches your problem. Enter values A, B, C, and D where needed. Use C as the scale factor for scaling. Use D as the total for a ratio split. Choose decimal precision. Press the calculate button. Review the result above the form. Download a CSV or PDF report when needed.
Understanding Ratios and Proportions
A ratio compares two values. It shows how much of one item relates to another item. Ratios appear in recipes, maps, mixtures, budgets, classroom tasks, and building plans. A proportion states that two ratios are equal. When one value is missing, proportional reasoning helps you find it.
Why This Calculator Helps
Manual ratio work is simple in theory. It can still become confusing with decimals, large numbers, or several comparisons. This calculator keeps each step visible. It reduces a ratio, solves a missing value, scales a ratio, compares two ratios, and splits a total by ratio parts. You can use it for study, shopping, planning, and checking work.
Common Real Life Uses
A cook may double a recipe while keeping the same flavor. A designer may scale a drawing without changing its shape. A buyer may compare prices by quantity. A teacher may check equivalent fractions. A contractor may divide materials by a fixed relationship. In each case, the calculator turns the relationship into clear numbers.
Working With Accuracy
The calculator accepts decimal values. It also lets you choose the rounding precision. This matters when results involve money, measurements, or scientific values. Cross multiplication is used for proportions. The same rule checks whether two ratios are equal. Simplification uses a common divisor after aligning decimal places.
Reading The Result
The result box appears before the form after calculation. It shows the main answer first. It then lists supporting values and steps. This format helps you copy the answer quickly. It also helps you understand why the answer is correct.
Exporting Your Work
Use the CSV option when you need spreadsheet data. Use the PDF option when you want a clean report. Both exports include the selected operation, the entered values, and the calculated result. They are useful for assignments, records, client notes, and repeated planning tasks.
Best Practice
Always enter values in the same unit. Do not mix inches with feet, grams with kilograms, or dollars with cents. Convert units first. Then calculate. Clear inputs create reliable proportions and better decisions. Review examples before entering final project data. Save exports whenever calculations must be shared. Recheck zero values because divisions by zero are invalid in proportions.
FAQs
What is a ratio?
A ratio compares two quantities. It shows how one value relates to another value. For example, 2:3 means two parts of one item relate to three parts of another item.
What is a proportion?
A proportion says two ratios are equal. The calculator checks this by cross multiplication. If both cross products match, the ratios are proportional.
Can this calculator simplify decimal ratios?
Yes. It aligns decimal places first. Then it converts the values into whole numbers and reduces them by a common divisor.
How do I solve a missing value?
Select the proportion format containing x. Enter the known values. The calculator cross multiplies and rearranges the formula to isolate the missing value.
What does compare ratios mean?
It checks whether two ratios describe the same relationship. The calculator compares A × D with B × C and reports whether they are equivalent.
How does the total split option work?
It divides a total according to ratio parts. For 3:2 and total 100, there are five parts. The shares are 60 and 40.
Why does the calculator reject zero sometimes?
Some values act as denominators. Division by zero is invalid. The calculator blocks those cases to prevent incorrect or undefined results.
Can I save the result?
Yes. After calculation, use the CSV button for spreadsheet data or the PDF button for a simple report.