Bunuel
Ronald scored 600 on the GMAT while Derek scored 338 on the GRE. Therefore, Ronald performed much better than Derek did.
Which of the following is the most serious flaw in the argument?
(A) The argument does not take into account the possibility that Ronald’s score could be a fluke.
(B) The argument does not take into account the past academic records of Ronald and Derek.
(C) The argument arrives at an extreme conclusion on the basis of unverified data.
(D) The argument assumes that standardized test scores are the best predictors of future success of an individual.
(E) The argument discounts the possibility that the GRE and the GMAT may have different scoring scales.
Official Explanation
Since this is a flaw question, you know that the stimulus will be worded in the form of an argument. So, the first step is to identify the conclusion and the evidence of this argument.
Conclusion (What is the argument stating):Ronald has performed better than Derek.
Evidence (Why is the argument stating this):Ronald scored 600 on the GMAT and Derek scored 338 on the GRE, and since 600 is more than 338, Ronald must have performed better.
But does this make sense? Those of you who are aware of the GRE scoring pattern would obviously know that a 338 (out of 340) on the GRE is a much better score than a 600 (out of 800) on the GMAT. However, the argument does not assume that you will know this or need you to know this.
For all you know, the GRE could be scored out of 1000 and the GMAT could be scored out of 2000. The important thing is to notice that the argument does not mention this fact, which will then take you to the assumption.
Assumption (the unstated evidence):The assumption now is fairly easy to predict—the GRE and the GMAT are scored on the same scoring scale. Only if this is assumed can the argument conclude what it is concluding; if you negate this fact then the argument will fall apart.
Flaw—The flaw will always question the assumption. It will raise doubts in your mind as to what if the assumption were not true. Out of the five options in the above argument, E does this best and, hence, is the correct answer. The argument does not take into account the possibility that the GRE and the GMAT may have different scoring scales—that a 338 on the GRE may actually be a better score than a 600 on the GMAT.
For clarity, let’s also take a look at the other options:
(A) It really doesn’t matter how Ronald arrived at that particular score as long as there is a possibility that this score could still be worse than Derek’s score.
(B) Past academic records are irrelevant because the argument is only concluding for the current tests taken by Ronald and Derek. The argument does not make a conclusion that Ronald, in general, is a better student than Derek.
(C) There is nothing in the argument to suggest that the data is unverified.
(D) The argument does not make any conclusions about how successful will the two candidates be in the future.
(E) The correct answer.