Factor an 8 out of both numbers: You're left with 5 and 12. The two numbers are relatively prime so we cannot factor any more out of both numbers. Thus 8 is our greatest common factor.
The common factors of 40 are 1,2,4,5,8,10,20,40 the common factors of 96 are 1,2,3,4,6,8,12,16,96 the common factors of both of them are 1,2,4,8 the GCF is 8 I hope this helped
