ADDITION & SUBTRACTION OF UNLIKE FRACTIONS

When adding or subtracting fractions with different denominators, we need to find a common denominator first. Let's learn how!

Key Steps:

Find the least common multiple (LCM) of the denominators

Convert each fraction to equivalent fractions using the LCM

Add or subtract the numerators

Simplify the answer if possible

Example 1: Addition

solve: 1/4+2/6

Find LCM of 4 and 6

4=2×2

6=2×3

LCM = 12

Convert fractions:

1/4=(1×3)/(4×3)=3/12

2/6=(2×2)/(6×2)=4/12

Add numerators:

3/12+4/12=7/12

Example 2: Subtraction

solve: 3/8-1/4

Find LCM of 8 and 4

8=2×2×2

4=2×2

LCM = 8

Convert fractions:

3/8 (already has denominator of 8)

1/4=(1×2)/(4×2)=2/8

Subtract numerators:

3/8-2/8=1/8

WORKSHEET

ADDITION & SUBTRACTION OF UNLIKE FRACTIONS