Subtracting Proper Fractions with Different Denominators: Step-by-Step Example
22 October 2026
When subtracting proper fractions with different denominators, it helps to break the process into clear steps. This makes it easier for your child to see how to work with fractions that do not share the same bottom number.
Worked example
Subtract 3/4 − 1/3
Step 1: Find the lowest common denominator.
The denominators are 4 and 3. The lowest common denominator is 12.
Step 2: Change both fractions to have denominator 12.
3/4 becomes 9/12. 1/3 becomes 4/12.
Step 3: Subtract the numerators. 9 − 4 = 5
Step 4: Write the answer. 5/12
The correct answer is 5/12.
| Step | Fraction 1 | Fraction 2 | Result |
|---|---|---|---|
| Original | 3/4 | 1/3 | |
| Common denominator | 9/12 | 4/12 | |
| Subtract numerators | 5/12 |
After following these steps, your child will be able to spot when fractions have different denominators and know how to handle them. Now, similar questions are ready for them to practise and build confidence.
