Q:

What is the GCF of 15 and 130?

Accepted Solution

A:
Solution: The GCF of 15 and 130 is 5 Methods How to find the GCF of 15 and 130 using Prime Factorization One way to find the GCF of 15 and 130 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 15? What are the Factors of 130? Here is the prime factorization of 15: 3 1 × 5 1 3^1 × 5^1 3 1 × 5 1 And this is the prime factorization of 130: 2 1 × 5 1 × 1 3 1 2^1 × 5^1 × 13^1 2 1 × 5 1 × 1 3 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 15 and 130 by multiplying all the matching prime factors to get a GCF of 15 and 130 as 25: Thus, the GCF of 15 and 130 is: 25 How to Find the GCF of 15 and 130 by Listing All Common Factors The first step to this method of finding the Greatest Common Factor of 15 and 130 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, 15 and 130: Factors of 15: 1, 3, 5, 15 Factors of 130: 1, 2, 5, 10, 13, 26, 65, 130 When you compare the two lists of factors, you can see that the common factor(s) are 1, 5. Since 5 is the largest of these common factors, the GCF of 15 and 130 would be 5. Find the GCF of Other Number Pairs Want more practice? Try some of these other GCF problems: What is the GCF of 114 and 79? What is the GCF of 8 and 1? What is the GCF of 42 and 77? What is the GCF of 37 and 124? What is the GCF of 64 and 44?