Do you always need to balance a chemical equation to find the percentage yield and limiting reagent?

[![The problems I'm trying to solve](https://i.stack.imgur.com/G46Vv.png)](https://i.stack.imgur.com/G46Vv.png)


I'm doing some problems through MIT open courseware and I've got one I'm absolutely stuck on. It details a three-step synthesis for hyperzine A, gives molecular weights and diagrams for individual reactants and the formula for the final result (huperzine A).


Then it asks you to find the limiting reagent for the first reaction. Every single source I've been able to find on this says that you need to balance the equation in order to do this, but the reactants seem so complicated I would have no idea how to begin doing this. It seems like we've got C10H16O(s) reacting with C8H5O4S2F6N(aq), but the result seems to be C11H15O3S1F3 (sorry, I have no idea how to format). They don't mention any other products, so my most obvious problem is that I have no idea what happens to the nitrogen, and even getting past that I have no idea how you would balance such a complicated reaction to work out mole ratios.


Question a asks about the limiting reagent, and you are only told about how much product is produced in question b, so I'm assuming to answer question a you don't need that information.


Furthermore, question b asks about percentage yield, and again, every source I've been able to find has stated you need to know the chemical equation (which I'm interpreting to mean 'balanced') to get this.


Since the only discussion of this problem I've seen online declares it 'easy' without any further explanation, I must be missing something big, but I've been bashing my head at this for many hours and have absolutely no idea where I'm going wrong. I've even accidentally spoiled myself on the answers at this point, but they haven't helped me to get any further with it.


