If you look at the question stem you'll notice that the sign of X is irrelevant as it would impact both sides equally. However, we need to know the signs of Z & Y to determine whether they reduce their respective sides of the equation or increase it.
Stmt 1 is insufficient since it doesn't tell us anything about the signs of X&Y. It only tells us the Z &Y relationship in absolute terms
Stmt 2 is insufficient since we don't care about X's sign
No additional info can be gained by looking at boths Stmts. Ans E
Mod inequalities - DS
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
