Question

What's the gcf of 32 and 81

Answer 1

Factors of 32: 1, 2, 4, 8, 16, 32
Factors of 81: 1, 3, 9, 27, 81

The greatest common factor of 32 and 81 is 1.

Answer 2

For this, you want to find the Factors, the Common ones and then the Greatest of those.
*Always list factor in pairs so that none are missed/left out

First, Factors of 32
1, 32
2, 16
4, 8

Now, Factors of 81
1, 81
3, 27
9

The next step is to highlight/circle the common factors

1,

As there is only one common factor, that is the greatest.
The GCF is 1