7, 14 and 21
1
7 
7
The GCF is 1.
The GCF is 7.
7 and 14, among others.
7. 7x3=21 7x8=56
63 - 1, 3, 7, 9, 21, 63 6 - 1, 2, 3, 6 the GCF is 3
Since 28 is a factor of 84, it is automatically the GCF.
The GCF of 7 and 28 is 7.
The greatest common factor of 3 and 7 is 1.