Find the GCF 80 , 36

$80$ , $36$

Step 1

Find the common factors for the numerical part:

$80, 36$

Step 2

The factors for $80$ are $1, 2, 4, 5, 8, 10, 16, 20, 40, 80$ .

The factors for $80$ are all numbers between $1$ and $80$ , which divide $80$ evenly.

Check numbers between $1$ and $80$

Find the factor pairs of $80$ where $x \cdot y = 80$ .

$\begin{array}{c} x & y \\ 1 & 80 \\ 2 & 40 \\ 4 & 20 \\ 5 & 16 \\ 8 & 10 \end{array}$

List the factors for $80$ .

$1, 2, 4, 5, 8, 10, 16, 20, 40, 80$

Step 3

The factors for $36$ are $1, 2, 3, 4, 6, 9, 12, 18, 36$ .

The factors for $36$ are all numbers between $1$ and $36$ , which divide $36$ evenly.

Check numbers between $1$ and $36$

Find the factor pairs of $36$ where $x \cdot y = 36$ .

$\begin{array}{c} x & y \\ 1 & 36 \\ 2 & 18 \\ 3 & 12 \\ 4 & 9 \\ 6 & 6 \end{array}$

List the factors for $36$ .

$1, 2, 3, 4, 6, 9, 12, 18, 36$

Step 4

List all the factors for $80, 36$ to find the common factors.

$80$ : $1, 2, 4, 5, 8, 10, 16, 20, 40, 80$

$36$ : $1, 2, 3, 4, 6, 9, 12, 18, 36$

Step 5

The common factors for $80, 36$ are $1, 2, 4$ .

$1, 2, 4$

Step 6

The GCF (HCF) of the numerical factors $1, 2, 4$ is $4$ .

$4$