# What is the GCF of 80 and 20?

#### Understand the Problem

The question is asking for the greatest common factor (GCF) of the numbers 80 and 20. We will find the factors of each number and identify the highest one they have in common.

$20$

The greatest common factor (GCF) of 80 and 20 is $20$.

#### Steps to Solve

1. List Factors of Each Number

First, we need to find all the factors of 80. The factors are the numbers that divide 80 without leaving a remainder.

For 80, the factors are:

• 1
• 2
• 4
• 5
• 8
• 10
• 16
• 20
• 40
• 80

Now we find the factors of 20:

• 1
• 2
• 4
• 5
• 10
• 20
1. Identify Common Factors

Next, we look for common factors from both lists. The common factors are the numbers that appear in both lists of factors.

The common factors of 80 and 20 are:

• 1
• 2
• 4
• 5
• 10
• 20
1. Determine the Greatest Common Factor

Finally, we need to identify the greatest (largest) number from the common factors we found:

The greatest common factor is 20.

The greatest common factor (GCF) of 80 and 20 is $20$.