ArunSharma12
statement 2: p < 0;
implies pq < 0I'm not precisely sure what you meant to write here, but when we know "p < 0" is true, we can't conclude that "pq < 0" is true without information about q.
There are a few ways one could approach the question - getting zero on one side in the question, then factoring, lets us see what kind of information we're looking for, for example. I'd say that's the most standard approach to take, and is the most flexible, so it's probably the best one to study, but Arun has posted a solution using that approach above, so I'll offer an alternative:
Is (p^2)(q) > (p)(q^2) ?
1. pq < 0
2. p < 0When we use Statement 1 alone, we can rephrase the question, by dividing by pq on both sides. Since pq is negative, we'll need to reverse the inequality when we do that. So when Statement 1 is true, our question becomes equivalent to "Is p < q?" Since we don't know if that's true, Statement 1 is not sufficient.
Similarly, using Statement 2 alone, we can rephrase the question by dividing by p on both sides, reversing the inequality when we do. The question then becomes "Is pq < q^2?" Again, we don't know if that's true -- it clearly can be, when q is positive (then the left side is negative, the right side positive) but it can be false if, say, p = -2 and q = -1.
Using both Statements, we know, from the above discussion of Statement 2, that our question becomes "Is pq < q^2?" If pq is negative, from Statement 1, the answer to this question must be yes, because q^2 is positive. So the answer is C.