What is the gcf of 18 27 and 36 and how did you do it

For the GCF, you want to perform the title backwards.

Write Factors of the numbers, find the Common ones and then the Greatest of those.

*It is good to write the factors in pairs to ensure none are left out

18

1, 18, 2, 9, 3, 6

27

1, 27, 3, 9

36

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

The factors common in all are 1, 3, & 9

Now, from these numbers, select the greatest - 9