Fraction Calculator
Add, subtract, multiply and divide fractions.
- Mixed number
- 5/6
- Decimal
- 0.833333
- Unsimplified divisor used
- 1
How this calculator works
For addition and subtraction the fractions are brought to a common denominator. Multiplication multiplies straight across, and division multiplies by the reciprocal. The answer is reduced by the greatest common divisor.
Formula
a/b + c/d = (ad + cb) ÷ bd; a/b ÷ c/d = ad ÷ bc
Example
1/2 + 1/3 = 3/6 + 2/6 = 5/6.
When to use it
- Homework and checking working
- Scaling recipes
- Measurements in woodworking and sewing
Frequently asked questions
How do I simplify a fraction?
Divide the numerator and denominator by their greatest common divisor. For 12/18 the divisor is 6, giving 2/3.
What is a mixed number?
A whole number plus a proper fraction, such as 1 1/2. It is another way of writing an improper fraction like 3/2.
Learn more
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