 # Subtracting Fractions (common or uncommon denominators)

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The following diagram shows how to subtract fraction with common denominators and uncommon denominators. Scroll down the page for more examples and solutions for subtracting fractions. ### Subtracting Fractions with Common Denominators or Like Denominators

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

Example : How to subtract fractions with common denominators.

### Subtracting Fractions With Uncommon Denominators or Unlike 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.

Example:

Evaluate Solution:

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. How to subtract fractions with uncommon denominators?

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