The greatest number that divides 30 and 60 without leaving a remainder is its GCF.
Find the GCF of 30 and 60 by listing their factors. We get the following:
The factors of 30 are: 1, 2, 3, 5, 6, 10, 15, 30
The factors of 60 are: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60
Since the greatest common factor of the two numbers is 30, then the greatest number that divides 30 and 60 without remainder is 30.