The common factors of 4 and 16 are: 1, 2, 4.
http://wiki.answers.com/Q/What_are_the_factors_of_...

One way to approach this is to look at the difference between 14 and 16, which is 2. The greatest common factor of two numbers cannot be larger than the difference between the two
http://wiki.answers.com/Q/What_is_the_greatest_com...

The GCF of 16 and 120 is 8.
http://wiki.answers.com/Q/What_is_the_greatest_com...

16 = 2 4 10 = 2 × 5
http://wiki.answers.com/Q/What_is_the_prime_factor...
