30 over 108 is a fraction. A fraction does not (cannot) have a GCF.
The GCF is 6.
The GCF is 54.
The GCF is 36.
The GCF is 27.
The GCF is 4.
The GCF is 12.
The GCF is 108.
30/108 = 5/18
GCF of 108 and 360 is 36.
30/108 = 5/18
480/1200 = 2/5 The GCF of 480 and 1200 is 240. 84/108 = 7/9 The GCF of 84 and 108 is 12.
The GCF is 12.