Ratio & Proportion Calculator

Simplify ratios, solve proportions and share an amount in a given ratio, with the working laid out clearly. Try “divide 240 in the ratio 3:5” to see the parts, the value of one part and the shares.

Try an example:

How the Ratio & Proportion Calculator works

  1. Add the ratio parts together to get the total number of parts (3 + 5 = 8).
  2. Divide the amount by the total parts to get the value of one part (240 ÷ 8 = 30).
  3. Multiply each ratio number by that value to get each share (90 and 150).

Frequently asked questions

How do you simplify a ratio?

Divide every number in the ratio by their greatest common factor, so 12:18 becomes 2:3.

How do you solve a proportion?

Cross-multiply: if a/b = c/d then a × d = b × c, then solve for the unknown.

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