do eight and six have any common multiples

In short, yes they do. The common multiples are 24,48,72,96.... you can find a multiple of a number when you multiply that number and another whole number together. So for instance, if you want to find the multiples of 6, just go through the 6 times table. So if you know your times tables, the products of the multiplication tables are all that number's multiples. If you are interested in finding the Least Common Multiple (LCM) between two or more numbers, you are looking for the lowest multiple that those two numbers share (0 does not count). There are a couple ways of doing that. One includes finding the prime factors of the two numbers. I can explain that further if you wish, but if you are not familiar with finding prime factors, then you might want to try to find the Least Common Multiple a different way. You can take the larger number (in this case the 8) and go through the 8 times table as follows... 8x1 = 8 (does 6 divide evenly into 8? if so, that's your LCM, if not then just continue) 8x2 = 16 (does 6 go evenly into 16? No, so we must continue 8x3 = 24. Does 6 go evenly into 24? Yes, therefore 24 is your least common multiple. Now that you found your least common multiple, you can find all the multiples of 6 and 8 by multiplying 24 by 2,3,4,5,6,7,and so on. A little trick when finding the least common multiple is that the least common multiple will never be more than the product of the two numbers. So in this case, we knew that the least common multiple was either 6x8 which is 48, or less. And in this particular case, although 48 is a common multiple, we found out that 24 was a smaller multiple. Hope this helps. It's difficult to explain in writing, but if you are still confused about something, let me know what specifically you're confused on and I'll try to clarify it.