Question

Whats the greatest common factor of 18 and 27 and 54

Answer 1

Answer: 9

Step-by-step explanation:

From doing the math I think it should be 9

Answer 2

Start with the smallest number, 18:

      The factors of 18 are: 1, 2, 3, 6, 9, 18.

So the GCF for all three must be one of those.

Now consider the next smallest number.  Of the factors of 18, only these are also factors of 27:

    1, 3, 9

Now consider the last number, 54.  Of the remaining factors, 9 is the greatest and 9 goes into 54.

The GCF is 9.

By starting with the smallest number, you usually limit how many factors you'll ever need to consider.