12 = 1 x 22 x 3
15 = 1 x 3 x 5
20 = 1 x 22 x 5
There is no need to factor 30; at this point, the GCF is already 1 (since 12 has no 5's, 15 has no 2's, and 20 has no 3's).
The Greatest Common Factor of 12, 44, 15: 1
the greatest common factor of 6,12, and 15 is 3.
3
The greatest common factor of the numbers 15 and 12 is 3.
The GCF is 15.
3
3
1
The GCF is 3.
1
15
It is: 3