Why is a number that is divisible by $2$ and $3$, also divisible by $6$? Why is it that a number such as $108$, that is divisible by $2$ and $3$, is also divisible by $6$? 
Is this true that all numbers divisible by two integers are divisible by their product?

N is divisible by 2 and 3, so N=2n or N=3m, so it includes 2 and 3 in its factors, which tells us it includes 6.
Numbers divisible by two integers aren't always divisible by their product. For example, like 3 and 6. The number includes 3 and 6 in its factors, so it includes LCM(3, 6), which is 6.
