The GCF of 304 and 980 is 4.
The GCF is 4.
140 is the Greatest Common Factor of 280 and 980.
It is: 20
The GCF is 19.
The GCF is 304.
The GCF is 8.
The GCF of 252, 420, and 980 is 28.
The GCF is 8.
19
A couple of problems. You need at least two numbers to find a GCF and the GCF is by definition positive.
The GCF is 140.