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.