How to use
- Choose Simplify, Solve a : b = c : d or Divide by a ratio.
- Enter the ratio with colons, or fill in three of the four boxes of the proportion, or the total and the ratio.
- Read the result; proportions also show the cross-multiplication step.
Options explained
- Simplify
- All parts are turned into whole numbers and divided by their greatest common factor. Works with any number of parts, decimals (1.5 : 2.25 = 2 : 3) and fractions (1/2 : 1/3 : 1/6 = 3 : 2 : 1).
- Solve a proportion
- In a : b = c : d the product of the outer terms equals the product of the inner terms (a × d = b × c), so any one missing term can be found.
- Divide by a ratio
- Each share is the total × its part ÷ the sum of the parts. Results are exact; fractions are shown with their decimal value.
Examples
| Task | Input | Result |
|---|---|---|
| Simplify | 12 : 18 | 2 : 3 |
| Simplify | 0.75 : 1.25 | 3 : 5 |
| Solve | 3 : 4 = 9 : x | x = 12 |
| Solve | 2 : 3 = x : 7 | x = 14/3 ≈ 4.67 |
| Divide 120 | 1 : 2 : 3 | 20, 40, 60 |
Frequently asked questions
How do I scale a recipe with a ratio?
Use Solve. If 3 cups of flour need 2 cups of milk, enter 3 : 2 = 5 : ? to find the milk for 5 cups of flour.
Is a ratio the same as a fraction?
A two-part ratio a : b compares the parts, while the fraction a/(a + b) is one part of the whole. In 2 : 3, the first part is 2/5 of the total.
Can I enter more than two parts?
Yes, for Simplify and Divide — separate them with colons, like 2 : 3 : 5.
Privacy
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