Question: what is the greatest common factor of 16 and 56?
Answer: The prime factorization of 56 is: 2 x 2 x 2 x 7. The prime factors and multiplicities 16 and 56 have in common are: 2 x 2 x 2. 2 x 2 x 2 is the gcf of 16 and 56. gcf(16,56) = 8.