Least Common Multiple  of 8 and 20 is 40

How to find the Least Common Multiple of 8 and 20?

On this page below, we'll use the Prime Factorisation, and the List of Multiples method to find out the LCM of 8 and 20.

Follow the steps below, and let's calculate the LCM of 8 and 20.


Method 1 - Prime factorization

Step 1: Create a list of all the prime factors of the numbers 8 and 20:

Prime factors of 8

The prime factors of 8 are 2, 2 and 2. Prime factorization of 8 in exponential form is:

8 = 23

Prime factors of 20

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

20 = 22x51


Step 2: Identify the highest power of each prime number from the above boxes:

23, 51


Step 3: Multiply these values together:

23x51=40


Step 4: The result:

As seen on the calculation above, we have now obtained the LCM of 8 and 20.

The Least Common Multiple of 8 and 20 is 40.


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 8:

8, 16, 24, 32, 40, 48, 56, 64

Multiples of 20:

20, 40, 60, 80, 100


Therefore,

LCM(8, 20) = 40