Question: what is a common factor 8 and 6?
Answer: Find the common factor of 6 and 8. Factor of 8 = 1, 2, 4 and 8. Therefore, common factors of 6 and 8 = 1 and 2. [It can easily be shown that each common factor (1 and 2) divides the given numbers 6 and 8 exactly].