What is the greatest common factor of 6 and 15?

The greatest common factor (gcf) of 15 and 6 is 3.

Factors of 6:1,2,3,6

Factors of 15: 1,3,5,15

The greatest common factor of the numbers 6 and 15 is 3.
The GCF of 6 and 15 is 3. This gives you 2 and 5 respectively. You cannot get any more common factors that impact the end figure.
The GCF is 3.
Greatest common factor of 6 and 15 is 3.