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CalcVerse

Calculadora de proporciones

Solve proportions of the form A : B = C : D for any missing value, and simplify ratios to their lowest whole-number terms. Useful for scaling recipes, maps, images and mixtures.

La guía de abajo aún no está disponible en español y se muestra en inglés. La calculadora está totalmente traducida.

Cómo usar esta calculadora

  1. Choose which term is unknown.
  2. Enter the other three values.
  3. The missing value, the simplified ratio A : B and its decimal value are shown.

Fórmula

In a proportion, the cross products are equal, so any one term can be found from the other three.

A : B = C : D  ⇔  A × D = B × C
D = B × C / A

Example

  1. 3 : 4 = 9 : D.
  2. D = 4 × 9 / 3 = 12.
  3. Resize a 1920 × 1080 image to 1280 wide: height = 1080 × 1280 / 1920 = 720.

Preguntas frecuentes

How do I simplify a ratio?

Divide both terms by their greatest common factor. 18 : 24 → GCF 6 → 3 : 4. Decimal ratios are first scaled to whole numbers.

What's the difference between a ratio and a fraction?

A fraction compares a part to a whole; a ratio can compare any two quantities, including part to part (e.g. 2 boys : 3 girls).

How do I scale a recipe?

Set A : B as the original servings to an ingredient amount, enter the new servings as C, and solve for D.