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 Administrator
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#35166
Complete Question Explanation

Parallel Flaw—SN. The correct answer choice is (A)

Your task in this Parallel Reasoning – Flaw question is to select the answer choice containing a
flawed argument most similar in structure to the flawed argument in the stimulus. The argument in
the stimulus is conditional, and presents a Mistaken Reversal:

..... Premise: ..... paleomycologist ..... :arrow: ..... acquainted with scholarly publications

..... Premise: ..... acquainted with scholarly publications Mansour ..... :arrow:

..... Conclusion: ..... paleomycologist Mansour

Your prephrase is that the correct answer will also contain conditional reasoning flawed in the same
manner as the argument in the stimulus. The incorrect answer choices will not present a similarly
flawed structure.

Answer choice (A): This the correct answer choice. The conclusion in this choice results from a
Mistaken Reversal, as did the argument in the stimulus:

..... Premise: ..... flight delayed ..... :arrow: ..... connecting flights delayed

..... Premise: ..... connecting flight delayed Frieda ..... :arrow:

..... Conclusion: ..... flight delayed Frieda

Answer choice (B): The conclusion in this choice results from a Mistaken Negation:

..... Premise: ..... missed shift ..... :arrow: ..... work harder

..... Premise: ..... missed shift last week ..... :arrow:

..... Conclusion: ..... work harder last week

Answer choice (C): This answer choice has a new term, profit, in the conclusion.

Answer choice (D): The conclusion to this argument shifts the necessary condition from a statement
of eligibility, that all employees can participate in the retirement plan, to the idea that Gavin is not
simply eligible to participate in the plan, but that he actually participates.

Answer choice (E): This choice concludes that since one of its compound necessary conditions was
not the case (Global did not reduce passengers), then the other necessary condition was met (Global
reduced its fares).
 mpoulson
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#24634
Hello,

I wanted to understand why A is correct and not D. I may have diagrammed this incorrectly, but I thought it was D because it mistakenly reverses the time commitment with participation in the retirement plan assuming Gavin's participation. Additionally, from the method of abstraction it seemed similar in that it went from a generalized statement about all employees to a specific employee gavin. Please explain where I went wrong and why D is correct. Thank you.

- Micah
 David Boyle
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#24943
mpoulson wrote:Hello,

I wanted to understand why A is correct and not D. I may have diagrammed this incorrectly, but I thought it was D because it mistakenly reverses the time commitment with participation in the retirement plan assuming Gavin's participation. Additionally, from the method of abstraction it seemed similar in that it went from a generalized statement about all employees to a specific employee gavin. Please explain where I went wrong and why D is correct. Thank you.

- Micah

Hello,

Answer D is more about "can happen versus must happen", or "eligibility versus participation", while answer A chimes more with the Mistaken Reversal (or close to it) that is in the stimulus. The stimulus says,

Paleo. :arrow: reads other paleos.' stuff
Reads SOME other paleos.' stuff (subscript Mansour) :arrow: Paleo. (subscript Mansour)

Answer A could be diagrammed,

Previous flight delayed :arrow: later (connecting) flights delayed
SOME later connecting flight delayed (subscript Frieda) :arrow: previous flight delayed (subscript Frieda)

David
 ericau02
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#64406
Hi I got this correct but I left ac C as a contender bc I was unsure. I am not really understanding why C is incorrect in terms of your explanation. Can you pls elaborate?
 James Finch
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#64950
Hi Erica,

The issue in (C) is that it is a relativity flaw, where it conflates the idea of being more profitable (or less unprofitable) with being profitable in an absolute sense. The premises only show that the company will be more profitable, while the conclusion contends that it will definitely be profitable.

This is also very different from the flaw in the stimulus, which is that the conclusion is a Mistaken Reversal of the conditional logic in the premises.

Hope this clears things up!
 hope
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#72914
I do not see how the Administrator's diagram reflects a Mistaken Reversal. Can someone expand on the diagram so that I can get clarity. Is the second premise conditional? If so, why isn't something on the other side of its arrow? And also the conclusion. Why isn't it set up like the LR Bible teaches? Please explain.
 hope
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#72915
Could someone also do an Abstract Test on this stimulus? Thank you.
 Adam Tyson
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#72922
When the stimulus is conditional, Hope, the diagram IS the abstraction! You need to find an answer that diagrams the same way. Or, if you prefer a non-diagrammatic approach, try this abstraction:

"One thing requires another thing, and the second thing did happen here, so the first thing must have also happened."

That's a description of a Mistaken Reversal, which is what happened in our stimulus and in our diagram.
 yusrak
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#75497
Hi,

I wanted to make sure I understood David Boyle's point regarding eligibility vs. participation.

I diagrammed answer choice D as:

Premise: all can participate :arrow: 1 year +
Premise: Gavin 3 years
Conclusion: :arrow: we can be sure Gavin participates

So although answer choice D structurally seems to be a mistaken reversal, it actually isn't. This is because the initial sufficient condition provided in the premise discusses the concept of eligibility; whereas, the conclusion is about participation. So although the term “participation” is used twice, it is referring to 2 different concepts and is thus not a true mistaken reversal. Is that why D is wrong?
 yusrak
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#75939
Hi,

After reviewing this question I was able to confirm that my reasoning above is correct. But upon reviewing this question I wasn't able to identify the flaw as a mistaken reversal. I just identified that the conclusion is flawed because it assumes a sufficient condition for the initial sufficient condition stated in the premise and thus assumes new information without establishing that information. I diagrammed the stimulus as follows:

(P = Paleomycologists. M = Mansour. PD = Paleomyocologist DeAngelis)

Premise 1: P :arrow: know all other P publications
Premise 2: M knows the publication of PD
Conclusion: M :arrow: P

I don't see the structural mistaken reversal in the stimulus. I just see that M is made sufficient for the initial sufficient condition stated in the premise. What am I missing?

Thanks in advance!
yusra

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