# What 2 or more numbers for a gcf represent?

The GCF is the largest whole number that is a factor for both of the numbers of interest. GCF is useful when simplifying fractions.

### What is the GCF of 188?

In order to have a GCF, you need 2 or more numbers, because GCF is the greatest common factor of 2 or more numbers. In order to find GCF, however, is to find the prime factorization of each number. For 188, it would be: 188: 2 * 2 * 47 Now you need another number to compare it to in order to find a GCF.