To calculate LCM of Fractions, you have to remember the following formula:

To calculate LCM of Fractions, you have to remember the following formula:

LCM of Fractions
= LCM of Numerators/HCF of De numerators

First you have to learn the trick to solve LCM and HCF of numbers quickly from the previous post.

Then you can easily solve this types of questions.

Let us take an example.

Find the LCM of 9/2, 3, 21/2.

Now let us apply the above given formula.
LCM of 9/2, 3, 21/2 = LCM of Numerators/HCF of De numerators= LCM of 9,3,21/HCF of 2,1,2

Now LCM of 9,3,21 as per the trick= 63
HCF of 2,1,2 as per the trick= 1
So LCM of 9/2, 3, 21/2= 63/1= 63 Ans.

Let us take another example.
Find the LCM of 5/8 and 1/2 ?

Solution: Now let us apply the above given formula.
LCM of Fractions = LCM of Numerators/HCF of De numerators
LCM of 5/8 and 1/2 = LCM of 5,1/HCF of 8,2
LCM of 5,1 = 5
HCF of 8,2 = 2
LCM of 5/8 and 1/2 = 5/2 Ans.

Note: the product of two numbers is equal to the product of their LCM and HCF.
A*B= LCM of A and B * HCF of A and B