Solution: The LCM of 1 and 20 is 20
Methods
How to Find the LCM of 1 and 20 by Listing Common Multiples
The first step to this method of finding the Least Common Multiple of 1 and 20 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 for those here:
What are the Multiples of 1?
What are the Multiples of 20?
Let’s take a look at the first 10 multiples for each of these numbers, 1 and 20:
First 10 Multiples of 1: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
First 10 Multiples of 20: 20, 40, 60, 80, 100, 120, 140, 160, 180, 200
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 1 and 20 are 20, 40, 60. Because 20 is the smallest, it is the least common multiple.
The LCM of 1 and 20 is 20.
Continue Practicing by Finding the LCM of Other Numbers
Take a look at some of our other walkthroughs, and you’ll be sure to be an expert at finding the LCM of any numbers in no time!
What is the LCM of 17 and 41?
What is the LCM of 91 and 57?
What is the LCM of 110 and 96?
What is the LCM of 95 and 50?
What is the LCM of 9 and 7?