To solve this, list all the known integer factors of 12: 3 and 4, 2 and 6, 1 and 12. Now, look at each factor (1, 2, 3, 4, 6, 12) and list a couple of the multiples of 6 which include: 6, 12, 18, 24, 30, etc. When you look back at the factors you notice that 1,2,3, and 4 are not a multiple of 6, therefore 1,2,3, and 4 are the numbers which is a factor of 12 and not a multiple of 6.
