Question: what is the greatest common factor of 24 and 28 using prime factorization?
Answer: The prime factorization of 28 is: 2 x 2 x 7. The prime factors and multiplicities 24 and 28 have in common are: 2 x 2. 2 x 2 is the gcf of 24 and 28. gcf(24,28) = 4.