Like and Unlike Fractions
Like Fractions
Fractions with the same denominators (bottom numbers) are called like fractions.
For example:
2/15, 7/15 and 13/15 are like fractions with the same denominators (bottom numbers).
Key Points
1. 1/4, 2/8, 3/12 etc. are not like fractions, although when simplified, they all result in 1/4.
2. 5/11 and 5/21 are not like fractions because numerators are same but denominator are not.
3. Whole number such as 3, 6, 7 etc. are like fractions since their denominators are considered as 1.
Unlike Fractions
Fractions with different denominators (bottom numbers) are called unlike fractions.
For example:
7/15, 11/5 and 13/11 are unlike fractions with the different denominators (bottom numbers).
Comparing Like Fractions
In case of like fractions, the fraction with the greater numerator is greater.
Example: Which is the larger fraction?
These fractions have same denominators, so we will compare the numerators.
Second fraction has larger numerator, so it is greater.
Comparing Unlike Fractions
Steps
1. Find the LCM (Least Common Multiple) of the denominators of the given fractions.
2. Convert the given fractions to equivalent fractions with denominator equal to the LCM (least common multiple) obtained in Step 1.
3. Compare the numerators of the equivalent fractions whose denominators are same.
Example: Compare 4/5 and 5/6.
Solution: Given fractions are unlike fractions.
LCM (least common multiple) of the denominators 5 and 6
LCM = 5 X 2 X 3 = 30
Now, we convert the given fractions to equivalent fractions with denominator 30.
We have,
Compare the numerators,
Since,
Therefore,
Example: Tom read 25 pages of a book containing 100 pages. Sam read 3/5 of the same book. Who read more?
Solution: Number of pages read by Tom = 25 pages
Number of pages read by Sam = 3/5 x 100
Hence, Sam read more pages.