What is Unlike Denominators?
Two fractions with nonidentical denominators are known as unlike denominators.
For example, to compare the fractions ^{3}⁄_{4} and ^{5}⁄_{7}, we first draw the fraction models and then compare the two fractions.
Converting unlike denominators to like denominators or common denominator:
Step 1: Find the least common multiple (LCM) of the denominators.
Multiples of 4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, ...
Multiples of 7: 7, 14, 21, 28, 35, 42, 49, 56, 63, 70,...
Step 2: Multiply both the numerator and the denominator of each fraction by a number to get the obtained LCM as the denominator.
Once the fractions have like denominators, they can be easily comapared, added or subtracted.
Example:
Compare 34 and 57 
Add 34 and57

Subtract 57 from 34

Fun Facts

Example:
^{4}⁄_{9} > ^{4}⁄_{11}