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The easiest way to find the least common multiple (LCM) is to just list out all the common multiples, like in the last lesson... and pick the smallest one!

Let's look at the ones we did in the last section:

Find the LCM of 2and 3:
 
1 )List the multiples of each:
2 :  2 , 4 , 6 , 8 , 10 , 12 , 14 , 16 , 18 , ...
3 : 3 , 6 , 9 , 12 , 15 , 18 , ...
 
2 )Look at the common multiples:
2 :  2 , 4 , ( 6 ) , 8 , 10 , ( 12 ) , 14 , 16 , ( 18 ) , ...
3 :  3 , ( 6 ) , 9 , ( 12 ) , 15 , ( 18 ) , ...
 
3 )Grab the least common multiple:
2 :  2 , 4 , (( 6 )) , 8 , 10 , ( 12 ) , 14 , 16 , ( 18 ) , ...
3 :  3 , (( 6 )) , 9 , ( 12 ) , 15 , ( 18 ) , ...  the LCM is 6
 
The LCM of 2and3is 6.

The special math notation for this is

LCM( 2 , 3 ) = 6