What goes into 15 and 56 together?

To find what goes into both 15 and 56, we need to determine their greatest common divisor (GCD). The factors of 15 are 1, 3, 5, and 15, while the factors of 56 are 1, 2, 4, 7, 8, 14, 28, and 56. The only common factor is 1, making the GCD of 15 and 56 equal to 1, which means they are relatively prime and share no other common divisors.