- PowerScore Staff
- Posts: 8287
- Joined: Feb 02, 2011
Here, the salesperson makes an argument comparing a person’s “old vacuum cleaner” to the Super XL vacuum cleaner. In doing so, the salesperson conducted an experiment: he first ran the old vacuum cleaner over a dirty carpet, and then ran the Super XL over the same carpet. Because the Super XL picked up dirt on the carpet left after the old vacuum cleaner was used on it, he concludes that the Super XL is the better vacuum.
The experiment’s structure definitely leaves much to be desired. Without getting bogged down in thinking about all of the reasons why the experiment was flawed, or how it should have been designed, go into the answer choices looking for one that describes how the amount of dirt picked up by the Super XL after the old vacuum cleaner had already gone over the same carpet does not
establish that the Super XL is the better vacuum cleaner.
Answer choice (A): The possibility in this answer choice would be relevant to an argument that concluded something like “the Super XL leaves no dirt behind,” but is not relevant to the comparison between the old vacuum cleaner and the Super XL.
Answer choice (B): There is no indication that the salesperson has made any inference whatsoever about the performance of the Super XL at a specific time in the future. All the stimulus discussed is the comparative performances of the machines at the time of the test.
Answer choice (C): This answer choice is inconsistent with the stimulus, which did not reach an absolute conclusion that the Super XL is the best vacuum cleaner. Instead, the conclusion simply compared the Super XL to the old vacuum cleaner.
Answer choice (D): This is a tricky answer choice. It is true that the author does not discuss the possibility that the old vacuum cleaner removed more dirt than the Super XL. However, that comparison, as to the total amount of dirt removed, is not the basis of the salesperson’s conclusion. Rather, the conclusion is based on the the Super XL removing dirt that the old vacuum cleaner did
not. To know which vacuum cleaner is superior, the experiment needed to test the vacuum cleaners under the same conditions. This answer choice does not describe that flaw, and so is incorrect.
Answer choice (E): This is the correct answer choice. As mentioned above, this answer choice is quite similar to answer choice (D). What makes this answer choice correct is the answer’s focus on the Super XL removing dirt that the old vacuum cleaner did not. If the Super XL and the old vacuum cleaner would have left behind the same amount of dirt when faced with the same carpet in the same state, then the salesperson’s conclusion would be shown false. The salesperson does not deal with this possibility, which is a flaw in the argument.