Question: what is the greatest common factor shared by 6 and 60?
Answer: The factors of 60 are 60, 30, 20, 15, 12, 10, 6, 5, 4, 3, 2, 1. The common factors of 6 and 60 are 6, 3, 2, 1, intersecting the two sets above. In the intersection factors of 6 ∩ factors of 60 the greatest element is 6. Therefore, the greatest common factor of 6 and 60 is 6.