Solution: The GCF of 88 and 99 is 11
Methods
How to find the GCF of 88 and 99 using Prime Factorization
One way to find the GCF of 88 and 99 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 88?
What are the Factors of 99?
Here is the prime factorization of 88:
2
3
×
1
1
1
2^3 × 11^1
2 3 × 1 1 1
And this is the prime factorization of 99:
3
2
×
1
1
1
3^2 × 11^1
3 2 × 1 1 1
When you compare the prime factorization of these two numbers, you can see that there are matching prime factors. You can now find the Greatest Common Factor of 88 and 99 by multiplying all the matching prime factors to get a GCF of 88 and 99 as 121:
Thus, the GCF of 88 and 99 is: 121
How to Find the GCF of 88 and 99 by Listing All Common Factors
The first step to this method of finding the Greatest Common Factor of 88 and 99 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, 88 and 99:
Factors of 88: 1, 2, 4, 8, 11, 22, 44, 88
Factors of 99: 1, 3, 9, 11, 33, 99
When you compare the two lists of factors, you can see that the common factor(s) are 1, 11. Since 11 is the largest of these common factors, the GCF of 88 and 99 would be 11.
Find the GCF of Other Number Pairs
Want more practice? Try some of these other GCF problems:
What is the GCF of 60 and 132?
What is the GCF of 150 and 140?
What is the GCF of 80 and 17?
What is the GCF of 9 and 65?
What is the GCF of 115 and 74?