akhp -- your equations are correct, but you'll find that these problems will become a LOT easier if you take the time to learn how to use the double set matrix.
i wanted to comment on this (emphasis mine):
akhp77 Wrote:Statement 1 and 2
Solve for H and P and find P/H; However, Not possible to eliminate N
Not Sufficient
unless i'm misunderstanding your writing, it appears that you have an implicit assumption that, if you are to find the ratio P/H, then you must find the INDIVIDUAL values of P and H.
this is a bad mistake -- in many (if not most) data sufficiency problems that call for combinations of variables, you'll be able to find the combination WITHOUT finding the individual variables.
the trademark of the test -- especially on harder problems -- is to give problems on which you can find the combination,
even though you CAN'T find the variables themselves!
i.e., if there were a situation in which you can find the ratio P/H, you would most likely be able to find at a ratio without the actual values of P and H -- and, in all probability, you'd be able to find that ratio even if P and H themselves were still undetermined.
the answer to this problem is (e), meaning that you can't find anything in this problem anyway, so this observation is irrelevant to the problem at hand. however, if you walk into every data sufficiency problem thinking that you should always solve for individual variables, you will be in for a rude surprise (if not several rude surprises).