Fraction Calculator
Do math with fractions step by step. Enter two fractions, choose the operation, and get the simplified result, the mixed number, and the decimal value.
Result
19/12
3/4 + 5/6 = 38/24 = 19/12
Check the highlighted fields to see your result.
- Mixed number
- 1 7/12
- Decimal
- 1.5833
Results are estimates for information only and do not constitute financial, medical, or legal advice.
How each operation works
- Add and subtract: the fractions need a common denominator. Multiply each numerator by the other denominator, add or subtract, and multiply the denominators.
- Multiply: multiply the numerators together and the denominators together.
- Divide: flip the second fraction and multiply.
In every case, the result is then simplified by dividing the top and bottom by their greatest common divisor.
The formulas
a/b + c/d = (a × d + c × b) / (b × d)
a/b ÷ c/d = (a × d) / (b × c)
Worked example
Add 3/4 and 5/6.
- Numerator: 3 × 6 + 5 × 4 = 18 + 20 = 38.
- Denominator: 4 × 6 = 24. So 3/4 + 5/6 = 38/24.
- Simplify: the greatest common divisor of 38 and 24 is 2, so 38/24 = 19/12.
- As a mixed number: 19 ÷ 12 = 1 with 7 left over, so 1 7/12, or 1.5833 as a decimal.
Frequently asked questions
What is a mixed number?
It is a whole number plus a proper fraction. For example, 19/12 is the same as 1 7/12: one whole (12/12) and 7/12 more. The calculator shows the mixed number when the result is greater than 1 or less than −1.
How do I simplify a fraction?
Divide the numerator and the denominator by their greatest common divisor. For 38/24, the greatest number that divides both is 2, so it simplifies to 19/12. The calculator always shows the simplified result.
How do I enter a negative fraction?
Put the minus sign in the numerator, for example −3 over 4. The result also shows the sign in the numerator.