# What is the GCF of 42 and 90?

The greatest common factor(GCF) of two numbers 42 and 90 is the largest possible number which divides both the numbers exactly.

## Answer: GCF of 42 and 90 is 6

Let's see how to find the GCF of 42 and 90

## Explanation:

The greatest common factor of two numbers is the largest possible number which divides both the numbers exactly without any remainder. The GCF also sometimes referred as to HCF(highest common factor).

## Common ways to Find GCF of 42 and 90

- Listing the Common Factors Method
- Long Division Method

### Method 1: GCF of 42 and 90 by Listing the Common Factors

In this method, we list all the factors of 42 and 90, then identify the common factors.

The highest among the common factors is the GCF of 42 and 90.

The factors of 42 are **1,** **2,** **3,** **6,** 7, 14, 21, 42

The factors of 90 are **1,** **2,** **3,** 5, **6,** 9, 10, 15, 18, 30, 45, 90

Common Factors of 42 and 90: 1, 2, 3, 6.

Greatest common factor= maximum(1, 2, 3, 6) = 6

GCF of 42 and 90 is 6

### Method 2: GCF of 42 and 90 by Long Division

- Step 1: Divide 90 by 42 and check the remainder.
- Step 2: Make the remainder of the above step as the divisor and the divisor of the above step as the dividend and perform the long division again.
- Step 3: Continue till you get the remainder as 0

Whichever method we opt for, the solution to our question GCF of 42 and 90 is the same.