Solution: The GCF of 11 and 30 is 1
Methods
How to find the GCF of 11 and 30 using Prime Factorization
One way to find the GCF of 11 and 30 is to compare 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 11?
What are the Factors of 30?
Here is the prime factorization of 11:
1
1
1
11^1
1 1 1
And this is the prime factorization of 30:
2
1
×
3
1
×
5
1
2^1 × 3^1 × 5^1
2 1 × 3 1 × 5 1
When you compare the prime factorization of these two numbers, you can see that there are no matching prime factors. When this is the case, it means that there are no common factors between these two numbers. As a result, the GCF of 11 and 30 is 1.
Thus, the GCF of 11 and 30 is: 1
How to Find the GCF of 11 and 30 by Listing All Common Factors
The first step to this method of finding the Greatest Common Factor of 11 and 30 is to find and list all the factors of each number. Again, you can see how this is done by looking at the “Factors of” articles that are linked to above.
Let’s take a look at the factors for each of these numbers, 11 and 30:
Factors of 11: 1, 11
Factors of 30: 1, 2, 3, 5, 6, 10, 15, 30
When you compare the two lists of factors, you can see that the only common factor is 1. So, in this case, the GCF of 11 and 30 is 1.
Find the GCF of Other Number Pairs
Want more practice? Try some of these other GCF problems:
What is the GCF of 40 and 45?
What is the GCF of 15 and 49?
What is the GCF of 145 and 109?
What is the GCF of 31 and 37?
What is the GCF of 12 and 133?