Solution: The LCM of 64 and 84 is 1344
Methods
How to find the LCM of 64 and 84 using Prime Factorization
One way to find the LCM of 64 and 84 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 64?
What are the Factors of 84?
Here is the prime factorization of 64:
2
6
2^6
2 6
And this is the prime factorization of 84:
2
2
×
3
1
×
7
1
2^2 × 3^1 × 7^1
2 2 × 3 1 × 7 1
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, 7
2
6
×
3
1
×
7
1
=
1344
2^6 × 3^1 × 7^1 = 1344
2 6 × 3 1 × 7 1 = 1344
Through this we see that the LCM of 64 and 84 is 1344.
How to Find the LCM of 64 and 84 by Listing Common Multiples
The first step to this method of finding the Least Common Multiple of 64 and 84 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, 64 and 84:
What are the Multiples of 64?
What are the Multiples of 84?
Let’s take a look at the first 10 multiples for each of these numbers, 64 and 84:
First 10 Multiples of 64: 64, 128, 192, 256, 320, 384, 448, 512, 576, 640
First 10 Multiples of 84: 84, 168, 252, 336, 420, 504, 588, 672, 756, 840
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 64 and 84 are 1344, 2688, 4032. Because 1344 is the smallest, it is the least common multiple.
The LCM of 64 and 84 is 1344.
Find the LCM of Other Number Pairs
Want more practice? Try some of these other LCM problems:
What is the LCM of 60 and 23?
What is the LCM of 10 and 42?
What is the LCM of 119 and 127?
What is the LCM of 145 and 46?
What is the LCM of 135 and 52?