# What is the GCF of 30 and 40?

Greatest Common Factor of two or more numbers is the largest possible number which divides the given numbers exactly without any remainder.

## Answer: GCF of 30 and 40 is 10

Two methods to find the GCF of 30 and 40 are explained below.

## Methods to find GCF of 30 and 40

- GCF of 30 and 40 by Prime Factorization
- GCF of 30 and 40 by Common Factors

### Method 1: GCF of 30 and 40 by Prime Factorization

Let us represent 30 and 40 as a product of its prime factors.

Prime factorization of 30 = 2 × 3 × 5

Prime factorization of 40 = 2 × 2 × 2 × 5

The common factors in the prime factorization of 30 and 40 are 2 and 5

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

This means GCF of 30 and 40 is 2 × 5 = 10

### Method 2: GCF of 30 and 40 by Listing the Common Factors

Follow the steps given below to find the GCF of 30 and 40 by Listing the Common Factors.

Step 1: List the factors of 30 and 40

Step 2: Identify the common factors of 30 and 40

Step 3: GCF of 30 and 40 is equal to the highest factor among the common factors of 30 and 40

So, GCF of 30 and 40 is 10

You can find the GCF in any of the above methods but the solution will be the same, that is, GCF of 30 and 40 is 10