THE BEST ANSWER IS E. THE BEST ANSWER IS E.

4. The best answer is E. We need to find the value of X + Y since Z is already given to us. Statement (1) is insufficient since we need the sum of X and Y. Statement (2) can be written as: 3X – 3Y = 15  X – Y = 5, you can see that both statements are the same and therefore more sufficient data is required.