Question

Whats the greatest common factor of 13 and 26 .

Answer 1

2 x 13=26
1 x 26= 26
answer is 26

Answer 2

multiply 2 and 13 to get:26 GCF or greatest common factor 
multiply 1 and 26 to get 26 GCF or Greatest Common Factor

Here is an example, 16 and 12 they one number in common but mainly they have a lot more, 16 is related to 4 as 12 i also related to 4 meaning that your GCF

I hope that is help☺