# Question #fb025

##### 2 Answers

see below

#### Explanation:

The lowest common multiple of two numbers is the smallest number both will divide into exactly.

For instance

because 6 is the smallest number that BOTH

there are several methods to go about find the

here I will illustrate just two

**method 1**

The simplest way is just to write down the multiples of both numbers and then pick out the common ones and hence the lowest is identified easily.

lcm(4,12)#

multiples of

multiples of

the common multiples are highlighted in red

common multiples

**method 2**

for two numbers

The second method uses the relationship

this is particularity useful when the numbers are too large for listing the multiples.

so

the third method using prime factors has been covered elsewhere

L C M : The smallest positive number that is a multiple of two are more numbers.

To find the L C M of 4, 10 :

Multiples of 4 are 4 8 12 16 **20** 24 28 32 36 40 and so on.

Factors of 10 = 10 **20** 30 40 and so on.

There is a match @ **20** which is the L C M

#### Explanation:

L C M : The smallest positive number that is a multiple of two are more numbers.

L C M of 3 & 5 is 15, because 15 is a multiple of 3 & 5. Other common multiples include 30, 45, etc., but they are not the smallest.

To find the L C M of 4, 10 :

Multiples of 4 are 4 8 12 16 **20** 24 28 32 36 40 and so on.

Factors of 10 = 10 **20** 30 40 50 60 and so on.

There is a match @ **20** which is the least common multiple.