Mix them as per instructions, then tinker with that recipe if you think they want more, or less, but give them time to really show signs of unhappiness before screwing around.. When you're using a package like that, the NPK numbers can be ignored in a way..
What they pertain to though is the percentage of the atomic mass of each element in an active molecule/ion of fertilizer in pure chemical form like KNO3 (potassium nitrate) etc, or a summed average in the case of complex mixes..
pH is important though.. If your pH is off then the availiability of the nutrients will get locked up regardless of how you mix your nutes..