How to Subtract Fractions Step by Step
Pennpaper Team
Subtracting fractions works almost exactly like adding fractions. Before you subtract, both fractions need to use the same size pieces.
Quick idea
Make the denominators match, subtract only the numerators, and keep the denominator unchanged.
Steps
- Check whether the denominators already match.
- If they do not match, find a common denominator.
- Rewrite both fractions using equivalent fractions.
- Subtract the numerators and simplify the result.
Worked example
Subtract one third from five sixths.
Full solution
Step-by-step walkthrough
Step 1
The denominators are 6 and 3. Use 6 as the common denominator.
Step 2
One third is the same as two sixths.
Step 3
Subtract 2 from 5 to get 3 sixths, then simplify to one half.
Common mistake
The denominator tells the size of the pieces, so it does not get subtracted. Only the numerators are subtracted after the denominators match.
Practice problems
- Subtract 3/4 - 1/4.
- Subtract 5/6 - 1/2.
- Subtract 7/8 - 1/4.
Answers
- 1/2
- 1/3
- 5/8
Ask Pennpaper to explain it live
If the steps make sense but you still feel stuck, start a Pennpaper lesson and ask the tutor to draw the problem on the whiteboard. Seeing the symbols move step by step is often what makes the concept click.