MultiConvers

Fraction Calculator

Enter two fractions and choose add, subtract, multiply or divide. The answer is reduced, then shown as a mixed number and a decimal.

How it works

Each part must be a whole number. Addition and subtraction use a common denominator: a/b ± c/d = (ad ± bc) / bd. Multiplication is ac/bd. Division is a/b ÷ c/d = ad/bc, which is undefined when the second numerator is 0.

The result is divided by the greatest common factor so 2/3 × 3/4 becomes 1/2, not 6/12. A zero denominator is rejected — the page never prints Infinity.

Formula

a/b + c/d = (ad + bc) / bd
a/b − c/d = (ad − bc) / bd
a/b × c/d = ac / bd
a/b ÷ c/d = ad / bc

Worked examples

  • Add 1/2 and 1/3

    1/2 + 1/3 → 5/6

  • Divide 1/2 by 1/4

    1/2 ÷ 1/4 → 2

Useful notes

  • This is fraction arithmetic, not a single fraction-to-decimal conversion. Use Fraction to Decimal when you only have one pair.
  • Improper results such as 19/12 are also written as 1 7/12.

FAQ

How do I add fractions with different denominators?

Cross-multiply onto a common denominator: 1/2 + 1/3 = (3 + 2) / 6 = 5/6.

How do I simplify the answer?

Divide the numerator and denominator by their greatest common factor. 6/12 and 1/2 are the same number; this tool keeps 1/2.

Can I enter a mixed number?

Not directly. Convert it first: 1 1/2 is 3/2. The result side will still show a mixed number when the answer is improper.

Related tools

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