Solution: The LCM of 140 and 145 is 4060
Methods
How to find the LCM of 140 and 145 using Prime Factorization
One way to find the LCM of 140 and 145 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 140?
What are the Factors of 145?
Here is the prime factorization of 140:
2
2
×
5
1
×
7
1
2^2 × 5^1 × 7^1
2 2 × 5 1 × 7 1
And this is the prime factorization of 145:
5
1
×
2
9
1
5^1 × 29^1
5 1 × 2 9 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, 5, 7, 29
2
2
×
5
1
×
7
1
×
2
9
1
=
4060
2^2 × 5^1 × 7^1 × 29^1 = 4060
2 2 × 5 1 × 7 1 × 2 9 1 = 4060
Through this we see that the LCM of 140 and 145 is 4060.
How to Find the LCM of 140 and 145 by Listing Common Multiples
The first step to this method of finding the Least Common Multiple of 140 and 145 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, 140 and 145:
What are the Multiples of 140?
What are the Multiples of 145?
Let’s take a look at the first 10 multiples for each of these numbers, 140 and 145:
First 10 Multiples of 140: 140, 280, 420, 560, 700, 840, 980, 1120, 1260, 1400
First 10 Multiples of 145: 145, 290, 435, 580, 725, 870, 1015, 1160, 1305, 1450
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 140 and 145 are 4060, 8120, 12180. Because 4060 is the smallest, it is the least common multiple.
The LCM of 140 and 145 is 4060.
Find the LCM of Other Number Pairs
Want more practice? Try some of these other LCM problems:
What is the LCM of 59 and 16?
What is the LCM of 142 and 98?
What is the LCM of 66 and 8?
What is the LCM of 102 and 14?
What is the LCM of 4 and 65?