How to put this in simple terms
Hey, grab that six-pack of Coca-Cola you've just bought that's waiting its turn to get stuck in the fridge. (If you don't have one, just humor me.) Got it? OK. Well, let's see. Unless you like lukewarm cola, you should still have all six there. Now, assuming Coke is the variable, 6 is the numerical coefficient of Coke in this case.
Not too complex, hm?