When subtracting fractions, you basically follow the same rules as for addition. Therefore, the same keys to successfully subtraction also apply. Make sure the “denominators are the same!”
Here is the rule for subtracting fractions…
- Build each fraction so that the denominators of each fraction are equal.
- Subtract the numerators of the fractions.
- The denominator of the answer will be the common denominator or the denominator of the built-up fractions, whichever applies.
- Reduce or simplify the answer, if needed.
Note: We Do Not Subtract denominators!
If you want to subtract fractions with the same denominator, simply omit Step #1.
3/5 – 1/5 =(3 – 1)/5 = 2/5
When the fractions have different denominators, you do all the steps.
1/2 – 1/3 = 3/6 – 2/6 =
= (3 – 2)/6 = 1/6
As usual, we cover all of the other things that could affect your understanding of subtracting fractions, just to be sure nothing is missed.
Supplemental Help
Subtracting Fractions Same Denominator