Solution: The LCM of 138 and 64 is 4416
Methods
How to find the LCM of 138 and 64 using Prime Factorization
One way to find the LCM of 138 and 64 is to start by comparing the prime factorization of each number. To find the prime factorization, you can follow the instructions for each number here:
What are the Factors of 138?
What are the Factors of 64?
Here is the prime factorization of 138:
2
1
×
3
1
×
2
3
1
2^1 × 3^1 × 23^1
2 1 × 3 1 × 2 3 1
And this is the prime factorization of 64:
2
6
2^6
2 6
When you compare the prime factorization of these two numbers, you want to look for the highest power that each prime factor is raised to. In this case, there are these prime factors to consider: 2, 3, 23
2
6
×
3
1
×
2
3
1
=
4416
2^6 × 3^1 × 23^1 = 4416
2 6 × 3 1 × 2 3 1 = 4416
Through this we see that the LCM of 138 and 64 is 4416.
How to Find the LCM of 138 and 64 by Listing Common Multiples
The first step to this method of finding the Least Common Multiple of 138 and 64 is to begin to list a few multiples for each number. If you need a refresher on how to find the multiples of these numbers, you can see the walkthroughs in the links below for each number.
Let’s take a look at the multiples for each of these numbers, 138 and 64:
What are the Multiples of 138?
What are the Multiples of 64?
Let’s take a look at the first 10 multiples for each of these numbers, 138 and 64:
First 10 Multiples of 138: 138, 276, 414, 552, 690, 828, 966, 1104, 1242, 1380
First 10 Multiples of 64: 64, 128, 192, 256, 320, 384, 448, 512, 576, 640
You can continue to list out the multiples of these numbers as long as needed to find a match. Once you do find a match, or several matches, the smallest of these matches would be the Least Common Multiple. For instance, the first matching multiple(s) of 138 and 64 are 4416, 8832, 13248. Because 4416 is the smallest, it is the least common multiple.
The LCM of 138 and 64 is 4416.
Find the LCM of Other Number Pairs
Want more practice? Try some of these other LCM problems:
What is the LCM of 10 and 113?
What is the LCM of 142 and 95?
What is the LCM of 131 and 31?
What is the LCM of 149 and 145?
What is the LCM of 120 and 48?