A university study reported that between 1975 and 1983 the length of

Question

A university study reported that between 1975 and 1983 the length of average workweek in a certain country increased significantly. A governmental study, on the other hand, shows a significant decline in the length of average workweek for the same period. examination of the studies shows, however, that they used different methods of investigation; thus there is no need to look further for an explanation of the differences in the studies' results.

The argument's reasoning is flawed because the argument fails to

A. distinguish between a study produced for the purposes of the operation of government and a study produced as a part of university research.

B. distinguish between a method of investigation and the purpose of an investigation.

C. recognise that only one of the studies has been properly conducted.

D. recognise that two different methods of investigation can yield identical results.

E. recognise that varying economic conditions result in the average workweek changing in length.

Aj85 · Answer

Two different studies conducted by two different agencies provide contradictory results. The author rejects further investigations just because both studies applied different methods. Now that's a flaw in reasoning. 2 or more methods for study can give you same results. for example for calculating GDP economists use 3 different approaches - Income method , production method and expenditure method, and yet come to same results. Option D identifies the flaw and is the correct answer.

A. distinguish between a study produced for the purposes of the operation of government and a study produced as a part of university research. (wrong) - The author does in fact distinguish between studies and purpose of investigation is of the least concern.
B. distinguish between a method of investigation and the purpose of an investigation. (wrong) -Again the same; purpose is not the topic of concern, and flaw does not deals with not differentiating in purpose.
C. recognise that only one of the studies has been properly conducted. (wrong)- The author gives no such indication that only one study has been properly conducted) 
D. recognise that two different methods of investigation can yield identical results. - Correct !
E. recognise that varying economic conditions result in the average workweek changing in length. (again out of scope)

GMATmission · Answer

Hi Aj,

My doubt is that doesn't C and D mean the same thing. If D says that two different methods can yield different results and when we apply this reasoning to the argument, we can say that since both methods can yield same results, one of the methods may be wrong. Am I over thinking??

Aj85 · Answer

Hello,

No you have got to look at the paragraph minutely. The question asks 'The argument's reasoning is flawed because the argument fails to ____________"

Now Option if C were correct it will read 'The argument's reasoning is flawed because the argument fails to recognise that only one of the studies has been properly conducted.

This may be correct but we cannot say this with certainty. The argument never mentions that only One of the study was conducted properly. May be both of the studies were conducted improperly. If it is not told explicitly by argument, then we cannot take for-granted that this argument is flawed because only one of the study was wrong.

On the contrary, look at the wording of D. It is also asking a question but it limits the possibility of the potential flaw. The argument's reasoning is flawed because the argument fails to recognise that two different methods of investigation CAN yield identical results.

The word CAN in option D raises possibility of a flaw whereas option C raises possibility of a flaw by adding an unmentioned fact. Option C takes for-granted that only 1 study was conducted improperly. we can raise question on what is explicitly stated and not adding some extra facts to original premises.

manalq8 · Answer

I go with D. I don't think it is C because I can't see what it's basing its decision on which method is correct?and which one?!!!
any explanations are helpful

Capricorn369 · Answer

My answer is D because the conclusion says - 
Different methods of investigation is used thats why no need to look further for an explanation of the differences in the studies' results.

To fix this flaw - two different methods of investigation can yield identical results. Option D states it correctly.
Cheers!

DmitryFarber · Answer

This is actually an official question . . . from the LSAT! https://www.manhattanprep.com/lsat/foru ... -t309.html

The OA is D. The author assumes that the studies will necessarily have different results, and therefore concludes that we don't need to look elsewhere for an explanation of the differences. D points out this assumption.

C doesn't work because it isn't established that one of the studies was conducted improperly, so it's not something the author has failed to realize. If it were indeed true that one of the studies was bad, that would certainly weaken the argument, but that's not what we're looking for.

napolean92728 · Answer

The correct answer is  (D)  recognise that two different methods of investigation can yield identical results.
Reasoning for the correct answer: The argument concludes that there's "no need to look further for an explanation" simply because the studies used different methods of investigation. This assumes that different methods will necessarily produce different results. However, this ignores the possibility that well-designed studies using different methodologies could still arrive at the same conclusion if they're measuring the same phenomenon accurately. The fact that the studies used different methods doesn't automatically explain why they reached contradictory conclusions about the same time period.

Reasons for eliminating the incorrect options:

(A) is incorrect because distinguishing between government and university research is irrelevant to the logical flaw. The source of the studies isn't the issue; the problem is assuming that methodological differences alone explain contradictory results without considering that different methods could potentially yield the same results if both were valid.

(B) is incorrect because the argument doesn't confuse methods and purposes of investigation. The flaw is about assuming different methods necessarily lead to different results, not about mixing up methods with purposes.

(C) is incorrect because the argument doesn't need to recognize that one study was improperly conducted. The argument's flaw exists regardless of whether either study was properly conducted. The issue is the assumption that methodological differences automatically explain contradictory results.

(E) is incorrect because varying economic conditions aren't relevant to the logical flaw in the argument. The argument is about explaining the differences between study results, not about explaining why workweeks change in length. This answer introduces an external factor not addressed in the original argument.

A university study reported that between 1975 and 1983 the length of

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A university study reported that between 1975 and 1983 the length of

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