If you're looking for a GCF, you need at least two numbers to find one of those.
The GCF is 10.
It is 5
1,2,6,12
5
The answer is 5
5
The GCF is 1.
The GCF is 2.
It is 5
The GCF is 1.
The GCF would be 10.
The answer to the Gfc of these numerals is 10. Hope this helped.