Find 1/3 + 1/4.
- Use denominator 12: 1/3 = 4/12 and 1/4 = 3/12.
- Add the numerators: 4 + 3 = 7.
Answer: 7/12
Adding and Subtracting Unlike Denominators Worksheets
Practice adding and subtracting unlike denominators with equal parts, exact answers and worked examples.
Learn the skill
Adding and subtracting fractions with unlike denominators
Fractions can be added or subtracted when they refer to equal-sized parts of the same whole. Rewrite them with a common denominator, combine the numerators, and simplify the result.
A method you can use
- Find a common multiple of the denominators; the least common multiple often keeps numbers small.
- Multiply the numerator and denominator of each fraction by the same factor.
- Add or subtract numerators, keep the common denominator, and reduce if possible.
Worked examples
Find 5/6 − 1/4.
- Use denominator 12: 5/6 = 10/12 and 1/4 = 3/12.
- Subtract: 10/12 − 3/12 = 7/12.
Answer: 7/12
Find 3/4 + 5/8.
- Rewrite 3/4 as 6/8.
- 6/8 + 5/8 = 11/8; eight eighths make one whole.
Answer: 1 3/8
Try it yourself
Solve these before opening the answers. The printable sets below give you more practice.
1. Find 1/2 + 1/3.
Show answer and explanation
5/6
Rewrite as 3/6 + 2/6.
2. Find 7/8 − 1/4.
Show answer and explanation
5/8
Rewrite 1/4 as 2/8, then subtract 7/8 − 2/8.
Before you begin
Identify a numerator and denominator and recognize equal-sized parts.
Choose your level
- Easy: Use halves, thirds and fourths.
- Medium: Use more equal parts and larger denominators.
- Hard: Use improper fractions or combine two steps.
Questions and answer calculations checked on 2026-09-17. How we check worksheets. Free for personal and classroom use.
Preview and print an easy set
Try six questions below, or choose a full set at your level.
1
Calculate 1/2 + 1/3. Simplify.
2
Calculate 2/5 − 1/4. Simplify.
3
Calculate 2/4 + 1/5. Simplify.
4
Calculate 1/3 − 1/4. Simplify.
5
Calculate 2/3 + 1/4. Simplify.
6
Calculate 3/4 − 1/5. Simplify.
Answer Key
1. 5/62. 3/203. 7/104. 1/125. 11/126. 11/20