Quick answer: 1 1/2 + 2/3: write 1 1/2 as 3/2, use the common denominator 6 to get 9/6 + 4/6 = 13/6, which is 2 1/6 or about 2.166667.
How it's calculated
Adding and subtracting: rewrite both fractions over the lowest common denominator (the LCM of the denominators), then add or subtract the numerators: a/b + c/d = (a·(L/b) + c·(L/d)) / L.
Multiplying: multiply the numerators and the denominators, a/b × c/d = ac/bd. Dividing: multiply by the reciprocal, a/b ÷ c/d = a/b × d/c.
The result is reduced by dividing the top and bottom by their greatest common factor (GCF calculator). Mixed numbers like 2 1/6 are converted to improper fractions (13/6) before calculating.
Worked examples
- 1/2 + 1/3: 3/6 + 2/6 = 5/6 ≈ 0.833333
- 1 1/2 × 2/3: (3 × 2) / (2 × 3) = 6/6 = 1
- 3/4 ÷ 1/8: 3/4 × 8 = 24/4 = 6
Frequently asked questions
How do I enter a mixed number?
Type the whole number, a space and the fraction: 2 3/4. Negative mixed numbers start with a minus sign: -2 3/4.
Can I enter decimals?
Yes. 0.25 is read exactly as 1/4, and 1.5 as 3/2.
What is the simplest form?
The fraction whose numerator and denominator have no common factor except 1, such as 2/3 instead of 4/6.
How do I turn a fraction into a percentage?
Multiply the decimal by 100: 5/6 ≈ 0.8333 = 83.33%. The what percent calculator does this directly.
What is 1 1/2 + 2/3?
2 1/6. Over a common denominator of 6 that's 9/6 + 4/6 = 13/6.
How do I divide fractions?
Flip the second fraction and multiply. 3/4 ÷ 1/2 becomes 3/4 × 2, which is 1 1/2.