Wednesday, July 16, 2014

How to Find L.C.M by Division Method

What is the Division Method?

The Division Method is just the method we use to divide numbers. In this topic, you will use the division method to find the LCM. Remember that LCM stands for least common multiple.

Finding LCM by Division Method...

Let's take the two numbers 12 and 36.

Now write both of the numbers inside as if you were writing the dividend inside a box for division.
   _______
  {12, 36

[ Please don't mind my box... I tried my best  :) ]

Next, look for a prime number that at least one of the numbers is divisible by. In this case we have two even numbers, so let's try 2.

2  { 12, 36
2  {   6, 18
3  {   3,   9
    {   1,   3

As you can see, we know have our Multiples.
The last step is multiplication.

You need to multiply the outside numbers ( divisors ) and the last two dividends ( 1 and 3 ) together to get the LCM.

Divisors= 2,2,3
Dividends= 1,3

So...
2x2x3x1x3
4x3x1x3
12x1x3
12x3
=36
That means that the LCM for 12 and 36 equals 36!

Sheet 1 Finding LCM by Division Method

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