Discussion
Let ∇ denote a mathematical operation. Is it true that x ∇ y = y ∇ x for all x and y?
(1) 
(2) x ∇ y = x − y
| (A) | if statement (1) ALONE is sufficient to answer the question but statement (2) alone is not sufficient; |
| (B) | ... |
| (C) | ... |
| (D) | ... |
| (E) | ... |
| (F) | ... |
The solution is
Posted: 10/12/2013 15:43
You said that (2) answer the question with NO for all values of x and y, but it is not true. If x = y, then x-y = y-x = 0, answering the question with YES. So the correct answer should be A, no?!
Posted: 11/01/2013 14:40
Raquel, this question is invalid. We will fix it in the next update. Sorry for the confusion. In Data Sufficiency questions, Statements 1 and 2 should not contradict each other.