Fraction Calculator
Add, subtract, multiply and divide fractions, mixed numbers and decimals.
Answer
5/4
- As a mixed number
- 1 1/4
- As a decimal
- 1.25
- As a percent
- 125%
3/4 + 1/2 = 5/4, which is 1.25 as a decimal.
Calculation breakdown
| Step | Formula | Result |
|---|---|---|
| First fraction | 3/4 = 3/4 | 0.75 |
| Second fraction | 1/2 = 1/2 | 0.5 |
| Add over a common denominator | Common denominator 4: 3/4 + 2/4 = 5/4 | 1.25 |
How it works
Enter two fractions, mixed numbers, whole numbers or decimals, choose an operation, and the answer appears simplified with the steps below.
Worked example
3/4 + 1/2:
- Least common denominator of 4 and 2: 4
- Rewrite over 4: 3/4 + 2/4
- Add the numerators: 3 + 2 = 5, so the sum is 5/4
- 5 and 4 share no common factor, so 5/4 is already simplified
- As a mixed number: 1 1/4, as a decimal 1.25, as a percent 125%
Exact arithmetic
The calculator uses whole-number arithmetic with no rounding, so even very large fractions stay exact. It accepts up to 15 digits in each number.
Sources
Frequently asked questions
How do you add or subtract fractions with different denominators?
Find the least common denominator, rewrite each fraction over it, add or subtract the numerators, and simplify. OpenStax shows −1/4 + 1/6 using a denominator of 12, which gives −3/12 + 2/12 = −1/12. The calculator shows each of these steps.
How do you multiply fractions?
Multiply the numerators and multiply the denominators, then simplify. For 2/3 × 3/4 that is 6/12, which simplifies to 1/2.
How do you divide fractions?
Multiply the first fraction by the reciprocal of the second, which means flipping the second fraction upside down. OpenStax's example is 2/5 ÷ (−3/7) = 2/5 × (−7/3) = −14/15.
How do you enter a mixed number?
Type the whole number, a space, then the fraction, such as 1 3/4. The calculator turns it into the improper fraction (1 × 4 + 3)/4 = 7/4. A negative mixed number takes a minus sign in front, as in -1 3/4.
How do you turn a fraction into a decimal or a percent?
Divide the top number by the bottom number to get the decimal, then multiply by 100 for the percent. For 5/4 that is 1.25, or 125%. The decimal and percent are shown under every answer.
Can I enter decimals?
Yes. A decimal is converted to an exact fraction, so 0.75 becomes 75/100, which simplifies to 3/4. This avoids the rounding errors that floating-point arithmetic can add, so 0.1 + 0.2 is exactly 3/10.