JeffGuns wrote:
Dear GMAT Club community
During my GMAT preparation, I noticed that I often struggle with Data Sufficiency questions. The reason that I struggle is because of questions like the following:
Question stem: "Is X greater/better than Y? Subsequently I often find out that, with the information given in the two statements, it is possible to calculate the difference between X and Y. However, after making the calculations, I often find out that X is NOT greater than Y. This puts me in an insecure position, because I doubt whether I should answer that the information given is sufficient (answers A, B, C, or D), or that I should answer that the information given is insufficient (answer E). After all, the answer to the original question is the following: "No, X is NOT greater than Y". So I'm inclined to pick answer E (NOT sufficient).
Can somebody tell me which rule I should apply in these type of situations?
A definitive 'no' is as valid as a 'yes' in establishing sufficiency. The critical factor in GMAT Data Sufficiency is not whether the answer is positive or negative, but whether the data provided conclusively supports that answer. A consistent 'no' can effectively fulfill the question's requirement, confirming the sufficiency of the data.
1. YES/NO DS Questions:
In Yes/No Data Sufficiency questions, a statement is sufficient if the answer is always "yes" or always "no", whereas a statement is insufficient if the answer can be "sometimes yes" and "sometimes no".
2. VALUE DS QUESTIONS:
When a DS question asks about the value of some variable, then the statement is sufficient ONLY if you can obtain a single numerical value for this variable.
Ceck more here:
https://gmatclub.com/forum/avoiding-com ... l#p3317069Hope it helps.