 ## How to find the Least Common Multiple of 20 and 30?

On this page below, we'll use the Prime Factorisation, and the List of Multiples method to find out the LCM of 20 and 30.

Follow the steps below, and let's calculate the LCM of 20 and 30.

### Method 1 - Prime factorization

#### Step 1: Create a list of all the prime factors of the numbers 20 and 30:

##### Prime factors of 20

The prime factors of 20 are 2, 2 and 5. Prime factorization of 20 in exponential form is:

20 = 22x51

##### Prime factors of 30

The prime factors of 30 are 2, 3 and 5. Prime factorization of 30 in exponential form is:

30 = 21x31x51

22, 51, 31

22x51x31=60

#### Step 4: The result:

As seen on the calculation above, we have now obtained the LCM of 20 and 30.

The Least Common Multiple of 20 and 30 is 60.

### Method 2 - List of Multiples

Find and list multiples of each number until the first common multiple is found. This is the lowest common multiple.

#### Multiples of 20:

20, 40, 60, 80, 100, 120

#### Multiples of 30:

30, 60, 90, 120, 150

LCM(20, 30) = 60