Verbal questions from any Manhattan Prep GMAT Computer Adaptive Test. Topic subject should be the first few words of your question.
mokap25
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CR - Instructors please help!!! explain this qn - Mold. .

by mokap25 Mon Aug 15, 2011 9:51 am

Hi Instructors

The question is as follows, from one of the MGMAT tests:

Every year many people become ill because of airborne mold spores in their homes. After someone becomes ill, specialists are often hired to eradicate the mold. These specialists look in damp areas of the house, since mold is almost always found in places where there is substantial moisture. If one wishes to avoid mold poisoning, then, one should make sure to keep all internal plumbing in good condition to prevent leakage that could serve as a breeding ground for mold.

Which of the following is an assumption on which the argument depends?


A Mold itself does not create moisture.
B. Most homeowners know enough about plumbing to determine whether theirs is in good condition.
C. Mold cannot grow in dry areas.
D. No varieties of mold are harmless.
E. Mold spores cannot be filtered from the air.

I dont understand why Choice C is wrong. If one was to use the negation strategy - i,e if Mold CAN grow in dry areas, then all this explanation is naturally false, as it has nothing to do with moisture then...they are not related ie

And so to me it did seem like a key assumption here.

I narrowed down to the 2 key choices, but then picked C over the OA - which is A, and I want to know how to take calls when 2 choices are so close.

I am doing terribly on CR, somehow all MGMAt qns do have 2 choices which look close, and so would really appreciate some help by senior instructors and experts on the forum, on some strategy and tips for such types.

Thanks
Kaps
george.kourdin
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Re: CR - Instructors please help!!! explain this qn - Mold. .

by george.kourdin Mon Aug 15, 2011 11:46 pm

neither senior nor export but three things

1) find the conclusion of the argument. the underlying conclusion is that moisture causes mold.
2) an assumption on which the argument depends is going to be an assumption without which the conclusion will fall apart. usually there are a few types of such assumptions: assumptions that strengthen the causal relationship identified in the argument or assumptions that eluminate alternative conditions that would weaken this relationship. in other words, if our conclusion is that A causes B - i.e. moisture causes mold an assumption that is crucial for the argument would be one that state that C does not cause B or perhaps that B does not cause A.

if the causal relationship is reversed, the conclusion and thus, the argument falls apart. if mold itself creates moisture, then good luck trying to get rid of the supposed "cause" of the problem, when in reality, moisture is not the cause, it is the effect.

this is why A is correct.

C is confusing/counterintuitive, afterall as you said, it makes sense, but we need to be careful when we negate it. the argument deals with moisture causing mold. whether or not mold can grow in dry areas is somewhat irrelevant.
jnelson0612
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Re: CR - Instructors please help!!! explain this qn - Mold. .

by jnelson0612 Fri Oct 07, 2011 10:31 pm

Jamie Nelson
ManhattanGMAT Instructor