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Fraction Calculator

The Fraction Calculator performs addition, subtraction, multiplication and division with two fractions. Every result is simplified to lowest terms and also shown as a mixed number and a decimal.

What this means

A fraction shows parts of a whole, like 3/4 (three quarters). When you operate on two fractions, the calculator finds a common approach, computes the result, then reduces it — for example 4/8 becomes 1/2.

How we calculate it

Formula

a/b + c/d = (ad + cb) / bd. Multiplication: a/b × c/d = ac/bd. Division: a/b ÷ c/d = ad/bc.

Worked example

1/2 + 1/3:

  1. 1Common denominator: 2 × 3 = 6
  2. 2(1×3 + 1×2) / 6 = 5/6
  3. 35/6 is already in simplest form.

Important assumptions

  • Denominators must not be zero.
  • Results are shown simplified to lowest terms.

Frequently asked questions

How do I add fractions with different denominators?

Find a common denominator, convert each fraction, add the numerators, then simplify. This calculator does it for you.

How do I divide by a fraction?

Multiply by the reciprocal (flip the second fraction). For example, 1/2 ÷ 3/4 = 1/2 × 4/3 = 2/3.

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