Solution: The GCF of 143 and 143 is 143MethodsHow to find the GCF of 143 and 143 using Prime FactorizationOne way to find the GCF of 143 and 143 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 143?What are the Factors of 143?Here is the prime factorization of 143:111×13111^1 × 13^1111×131And this is the prime factorization of 143:111×13111^1 × 13^1111×131When 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 143 and 143 by multiplying all the matching prime factors to get a GCF of 143 and 143 as 20449:Thus, the GCF of 143 and 143 is: 20449How to Find the GCF of 143 and 143 by Listing All Common FactorsThe first step to this method of finding the Greatest Common Factor of 143 and 143 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, 143 and 143:Factors of 143: 1, 11, 13, 143Factors of 143: 1, 11, 13, 143When you compare the two lists of factors, you can see that the common factor(s) are 1, 11, 13, 143. Since 143 is the largest of these common factors, the GCF of 143 and 143 would be 143.Find the GCF of Other Number PairsWant more practice? Try some of these other GCF problems:What is the GCF of 51 and 88?What is the GCF of 3 and 11?What is the GCF of 22 and 119?What is the GCF of 117 and 123?What is the GCF of 68 and 137?