Fraction calculator
Add, subtract, multiply or divide two fractions. The calculator shows the answer before and after reducing, together with its decimal form.
The answer is 5/6, or 0.8333 as a decimal.
Formula
a/b and c/d are the two fractions. For addition and subtraction the common denominator is the product b · d.
How we got there
The calculator always reduces the answer to lowest terms by dividing the numerator and denominator by their highest common factor.
How to do fraction arithmetic by hand
- For addition, find a common denominator
The simplest choice is the product of the denominators: 1/2 + 1/3 gives a denominator of 6.
- Rewrite both fractions
1/2 = 3/6 and 1/3 = 2/6. The denominators now match.
- Do the arithmetic on the numerators
3/6 + 2/6 = 5/6. The denominator stays as it is.
- For multiplication and division no common denominator is needed
Multiply numerator by numerator and denominator by denominator. Division is multiplication by the reciprocal.
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Frequently asked questions
Put them over a common denominator, add the numerators and reduce. For 1/2 + 1/3 the answer is 5/6.
Multiply the first by the reciprocal of the second: 1/2 ÷ 3/4 = 1/2 · 4/3 = 2/3.
Yes. It also shows the unreduced form so the whole method is visible.
Convert it to an improper fraction first: 2 1/2 is 5/2, so numerator 5 and denominator 2.
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