The GCF can be the smaller one of the two numbers,
or else it can be a number smaller than either of them.
It can never be more than the smaller of the two numbers.
-- The GCF of 10 and 100 is 10 .
-- The GCF of 9 and 102 is 3 .
-- The GCF of 10 and any number more than 10
an never be bigger than 10 .