About the fraction calculator
Enter each fraction as a whole number, a numerator and a denominator. Leave the whole number at 0 for a plain fraction such as 3/4, or fill it in for a mixed number such as 2 1/2. Pick an operation and the calculator returns the answer in lowest terms.
The answer is shown three ways: as a simplified fraction, as a mixed number and as a decimal. For addition and subtraction the common denominator that was used is also shown.
A denominator can never be zero, and you cannot divide by a fraction whose value is zero. The calculator tells you when either happens instead of returning a wrong answer.
How each operation works
To add or subtract, rewrite both fractions over a common denominator, then combine the numerators. To multiply, multiply the numerators together and the denominators together. To divide, multiply the first fraction by the reciprocal of the second. Finally, divide the top and bottom by their greatest common factor.
Formula
- a/b + c/d = (a×d + c×b) ÷ (b×d)
- a/b × c/d = (a×c) ÷ (b×d)
- a/b ÷ c/d = (a×d) ÷ (b×c)
- Mixed number w n/d = (w×d + n) ÷ d
Example
1/2 + 1/3 = 3/6 + 2/6 = 5/6. And 2 1/2 × 1 1/3 = 5/2 × 4/3 = 20/6, which simplifies to 10/3 or 3 1/3.