The GCF of consecutive integers is 1.
Yes.
Their product.
Since 13 is a factor of 39, it is automatically the GCF.
The LCM is 156.
Since they have no common prime factors, their GCF is 1 and their LCD (LCM) is their product, 143.
The GCF is 12.The GCF is 12.
GCF of 12 and 12 is 12.
The GCF is... 12
GCF=12
The GCF is 12.
The GCF is 12.
The GCF is 12.