OML Search

Subtracting Fractions (with common or uncommon denominators)

Related Topics:
More Lessons for Arithmetic

Math Worksheets

Subtracting Fractions with Common Denominators

When we subtract fractions that have the same, or common denominators, we subtract only the numerators. The denominators stay the same.

Example :

The following video shows how to subtract fractions with common denominators.

Subtracting Fractions With Uncommon Denominators

To subtract fractions with uncommon denominators, we need to change the fractions to equivalent fractions with common denominators before we find the difference.

First, we would need to find the least common denominator (LCD), which is the LCM of the denominators.

Next, we write equivalent fractions using the least common denominator. Then, we proceed to subtract as before.





Step 1 : Find the LCD or LCM of 2 and 5

Multiples of 2: 2, 4, 6, 8, 10, 12

Multiples of 5: 5, 10, 15

The LCD or the Least Common Multiple of 2 and 5 is 10

Step 2 : Write both fractions as equivalent fractions with a common denominator of 10.

Step 3: Subtract the 2 equivalent fractions.

subtract fractions

The following video shows how to subtract fractions with uncommon denominators.

Rotate to landscape screen format on a mobile phone or small tablet to use the Mathway widget, a free math problem solver that answers your questions with step-by-step explanations.

You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

OML Search

We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.

[?] Subscribe To This Site

follow us in feedly
Add to My Yahoo!
Add to My MSN
Subscribe with Bloglines