What is Least Common Multiples ( LCM)

Introduction

Least Common Multiples or LCM is pretty much the same thing as common multiples. In finding the common multiples of a number, you just list the Times Table for that number. Well, when it comes to finding the LCM of two numbers you still write the Times Table of the numbers, but then you also have to look at the smallest or least multiple for both of the numbers that is common. That becomes your LCM.

Now that you know some basics on LCM, let's move on to a guided problem.

Finding the LCM!

Let's say that we have the two numbers 6 and 14. In order to find the LCM for these numbers, you need to first list their multiples. You do that by writing the Times Table for each number:

Times Table of 6:            Times Table of 14:

6 x 1= 6                               14 x 1= 14

6 x 2= 12                             14 x 2= 28

6 x 3= 18                             14 x 3= 42

6 x 4= 24                             14 x 4= 56

6 x 5= 30                             14 x 5= 70

6 x 6= 36                             14 x 6= 84

6 x 7= 42                             14 x 7= 98

6 x 8= 48                             14 x 8= 112

6 x 9= 54                             14 x 9= 126

6 x 10= 60                           14 x 10= 140

Now that we have listed the Times Table for each of these numbers, let's find the least common multiple for the numbers:

As you can see, the LCM is 42 because 6x7=42 and 14x3=42. 

Now wasn't that easy?!

Sheet 1 What is LCM