What is the greatest common factor of 27 and 72

The greatest common factor or GCF of 27 and 72 is 9

The reason being is because 9 is the biggest number that will divide into both 27 and 72

Looking for the greatest common factor of 27 and 72.

We look for numbers that can divide into 27 and 72 at the same time.

3 /      27              72
3 /      9                24
   /      3                  8               

No other number can go into 3 and 8 simultaneously so we stop.

GCF: We multiply the numbers before the stroke /

= 3 * 3 = 9

Greatest common factor = 9

I hope this is a bit clearer.