You need at least two numbers to find a GCF.
It is: 28 which is the greatest common factor of 56 and 84
The GCF is 20.
The GCF is 15.
The GCF is 1.
The GCF is 2.
The GCF is 16.
4x^3y
The GCF is 6.
The GCF is 12.
The GCF is 4.
The Greatest Common Factor of 122 and 144 is 2.
The greatest common factor of 32 and 144 is 16.