What will go into 8 and 24?

The numbers that go into both 8 and 24 are their common divisors. The common divisors of 8 and 24 are 1, 2, 4, and 8. Additionally, 8 is a factor of 24, since 24 can be divided evenly by 8. Thus, the greatest common divisor (GCD) of 8 and 24 is 8.