PrepTest 141, Section 4, 10. Vacuum cleaner salesperson: To prove…

How will the right answer fit in terms of support and conclusion?

Only the right answer will accurately describe a flaw in the argument, though it will also be the only one that accurately describes both the support and conclusion.

Highlight the main conclusion in the passage, if there is one:

the Super XL is the better vacuum.

Vacuum cleaner salesperson: [BACKGROUND]. [BACKGROUND]. [SUPPORT], proving [CONCLUSION].

You definitely need to catch that the conclusion makes a comparison between the two vacuums, which seems a little strong based on this one little experiment. Expect the right answer to tell us why that little experiment doesn’t really make a fair comparison.

Map the wording of the answers to the wording of the passage:

(A) …dirt remained in the carpet even after the Super XL had been used…

This would only map to a statement about picking up “all” the dirt or leaving “nothing” behind. Something like that. There’s no all-or-nothing statement in the passage. This doesn’t map to the comparison between the vacuums in the conclusion.

(B) …the Super XL will still perform better…when it is the same age…

The conclusion is in the present, so info about the future of these vacuum cleaners doesn’t line up at all.

(C) …it is the best vacuum cleaner available

I think only folks who aren’t reading carefully enough are picking this, since the author is clearly only comparing two vacuums. The “best vacuum cleaner available” isn’t ever mentioned or referenced.

(D) …the amount of dirt removed in the test by the old vacuum cleaner is greater…

This might sound super relevant at first, but the support in the passage is about the Super XL getting the dirt “left behind”. That’s not mentioning or relying on how much either vacuum picked up overall.

(E) …if the Super XL had been used first it would have left behind just as much dirt…

This is the only that talks about why the support sucks. It says if this person did the test differently, they easily could’ve gotten a different outcome. And then their conclusion would be shot.

(E) is the correct answer.

Common pattern/s in this question: The right answer was the only one that talked about the same comparison the passage talked about, without bringing in anything new. You’ll find that pattern holds pretty much every time the conclusion hinges on a comparison.