The Greatest Common Factor (GCF) of 15 and 31 is 1.
The GCF is 1.
The GCF is 31.
The GCF is 31.
The GCF is 1.
The GCF is 1.
The GCF is 1.
The GCF is 1.
The GCF of 31 and 6 is 1.
The GCF of 15 and 90 is 15.
The GCF is 31.
Since 15 is a factor of 60, it is automatically the GCF.
1 is the GCF of 33 and 31 because 31 is a prime number.