EVERYDAY / CORE MATHS

Fraction calculator

Add, subtract, multiply or divide two fractions and get the answer in lowest terms, as a mixed number and as a decimal.

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YOUR RESULT

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WORKED EXAMPLE

Fraction calculator: a worked example

With first numerator 1, first denominator 2, operation + Add, second numerator 1, second denominator 3, the result (simplified) is 5/6.

Inputs
First numerator1
First denominator2
Operation+ Add
Second numerator1
Second denominator3
Results
Result (simplified)5/6
Mixed number5/6
Decimal0.8333333333
Percentage83.33333333%
THE METHOD

How it works

Enter whole-number numerators and denominators. To add or subtract, the fractions are put over a common denominator; to divide, the second fraction is flipped and multiplied. The answer is reduced to lowest terms and shown as a mixed number when it is larger than one.

Formulaa/b + c/d = (ad + bc)/bd; a/b × c/d = ac/bd; a/b ÷ c/d = ad/bc; then divide top and bottom by their greatest common divisor.
ASSUMPTIONS

Assumptions and limits

  • Results are estimates based on the inputs and assumptions on this page, not professional advice.
  • Try this: use “Save scenario A”, change one input and compare the two results side by side.
QUESTIONS

Frequently asked questions

How is the result of the “Fraction calculator” calculated?

a/b + c/d = (ad + bc)/bd; a/b × c/d = ac/bd; a/b ÷ c/d = ad/bc; then divide top and bottom by their greatest common divisor. Enter whole-number numerators and denominators. To add or subtract, the fractions are put over a common denominator; to divide, the second fraction is flipped and multiplied. The answer is reduced to lowest terms and shown as a mixed number when it is larger than one.

What does the worked example show?

With first numerator 1, first denominator 2, operation + Add, second numerator 1, second denominator 3, the result (simplified) is 5/6. Mixed number: 5/6; Decimal: 0.8333333333; Percentage: 83.33333333%.

What assumptions and limits apply?

This is an estimate based on the inputs and assumptions shown on this page, not professional advice. Check anything with financial, health or safety consequences independently.

Is my data private?

Yes. Calculations run in your browser and your numbers are not sent to a server. A share link contains the inputs you choose to share, so check it before sending it to anyone.

FOR WEBSITE OWNERS

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