# What is the GCF of 15 and 25?

Greatest Common Factor: It is defined as the largest(greatest) possible number which divides the given numbers exactly, leaving the remainder as zero.

## Answer: GCF of 15 and 25 is 5

Two methods to find the GCF of 15 and 25 are explained below.

## Methods to find GCF of 15 and 25

- Prime factorization Method
- Listing the common factors method

### Method1: GCF of 15 and 25 by Prime Factorization

Here 15 and 25 are represented as a product of its prime factors.

Prime factorization of 15 is 3 × 5

Prime factorization of 25 is 5 × 5

Common factors = 5

GCF is the product of the factors that are common to both the given numbers.

GCF is 5

### Method2: GCF of 15 and 25 by Listing the Common Factors

Common Factors of 15 and 25: 1 and 5

The greatest common factor is 5

GCF of 15 and 25 is 5