Comprehensive Calculator Guide
The fraction calculator adds, subtracts, multiplies or divides two fractions and gives the answer in lowest terms, as a mixed number and as a decimal. For example 1/2 + 1/3 = 5/6, and 7/8 ÷ 1/4 = 7/2, or 3 1/2.
The four operations
To add or subtract, bring the fractions to a common denominator: (1×3 + 1×2) ÷ (2×3) = 5/6. Adding tops and bottoms directly (2/5) is wrong. To multiply, multiply tops and bottoms: 3/4 × 2/5 = 6/20 = 3/10.
To divide, multiply by the reciprocal of the second fraction: 7/8 ÷ 1/4 = 7/8 × 4 = 28/8 = 7/2. The calculator then divides top and bottom by their greatest common divisor and shows 7/2 as the mixed number 3 1/2.
How to Use
- 01Enter the first numerator and denominator.
- 02Pick the operation.
- 03Enter the second fraction to see the answer in lowest terms, as a mixed number and as a decimal.
Formula Used
a/b ± c/d = (ad ± cb) ÷ bd | a/b × c/d = ac ÷ bd | a/b ÷ c/d = ad ÷ bcPractical Examples
Example 1: adding
1/2 + 1/3 = 5/6 ≈ 0.8333.
Example 2: multiplying
3/4 × 2/5 = 3/10 = 0.3.
Example 3: dividing
7/8 ÷ 1/4 = 7/2 = 3 1/2 = 3.5.
Example 4: subtracting
5/6 − 1/4 = 14/24 = 7/12.
Important Tips
- Put a minus sign on the numerator for a negative fraction.
- Turn a mixed number into a fraction first: 2 1/3 = 7/3.
- Enter a whole number with a denominator of 1.
Common Mistakes to Avoid
- Adding numerators and denominators straight across.
- Flipping the first fraction instead of the second when dividing.
Frequently Asked Questions
- How do I add fractions with different denominators?
- Cross-multiply to a common denominator, add the numerators, then simplify.
- How do I divide fractions?
- Multiply the first by the reciprocal of the second.
- Is the answer simplified?
- Yes, it is reduced by the greatest common divisor.
- Why is a zero denominator rejected?
- Division by zero is undefined.