Find the first Three Common Multiples of: (a) 6 and 8 (b) 12 and 18

To find the first three common multiples of these numbers, we need to find the LCM of 6, 8 and 12, 18.

So, 6 can be written as,

6 = 2 * 3

8 = 2 * 2 * 2

So, LCM of 6 and 8 is = 2 * 3 * 2 * 2

= 24

So, the first three multiples are 24, 48, 72

In same manner, 

12 = 2 * 3 * 2

18 = 2 * 3 * 3

So, the LCM is = 2 * 3 * 3 * 2 

= 36

So, the first three multiples are, 36, 72, 108.