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
Step 2: Identify the highest power of each prime number from the above boxes:
22, 51, 31
Step 3: Multiply these values together:
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
Therefore,
LCM(20, 30) = 60