airplane mechanical problems

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airplane mechanical problems

by daretodream » Thu Feb 18, 2010 11:12 pm
Investigators concluded that human failure was not responsible for the fatal airplane crash last August, and since that time new and more stringent rules for identifying and reporting mechanical problems have been in effect. That accounts for the fact that reports of airplane mechanical problems have increased in frequency by 50 percent since last August.
Which one of the following is an assumption underlying the argument in the passage?
(A) Airplane travel is still relatively safe, despite the increase in reported mechanical problems.
(B) Mechanical problems in airplanes have increased dramatically since last August.
(C) Mechanical problems in airplanes have not increased by 50 percent since last August.
(D) Airlines are less reluctant to report mechanical problems than they previously were.
(E) Mechanical problems in airplanes have become easier to detect since last August.
Source: — Critical Reasoning |

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by komal » Thu Feb 18, 2010 11:36 pm
daretodream wrote:Investigators concluded that human failure was not responsible for the fatal airplane crash last August, and since that time new and more stringent rules for identifying and reporting mechanical problems have been in effect. That accounts for the fact that reports of airplane mechanical problems have increased in frequency by 50 percent since last August.
Which one of the following is an assumption underlying the argument in the passage?

(A) Airplane travel is still relatively safe, despite the increase in reported mechanical problems.
Incorrect : This does not talk about the cause of increased mechanical problems. Eliminated.

(B) Mechanical problems in airplanes have increased dramatically since last August.
Incorrect : It weakens the argument by providing an alternate cause for the stated effect.

(C) Mechanical problems in airplanes have not increased by 50 percent since last August.
Correct : If it is not human error then it should be mechanical error and the number of mechanical problems should not be more than that present earlier.

(D) Airlines are less reluctant to report mechanical problems than they previously were.
Incorrect : How does it matter if airlines are less reluctant or more reluctant? Eliminated.

(E) Mechanical problems in airplanes have become easier to detect since last August.
Incorrect : Clearly out of scope
Last edited by komal on Fri Feb 19, 2010 12:57 pm, edited 1 time in total.

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by thephoenix » Fri Feb 19, 2010 12:13 am
(A) Airplane travel is still relatively safe, despite the increase in reported mechanical problems
--> out of scope

(B) Mechanical problems in airplanes have increased dramatically since last August
--> this is a weaken

(C) Mechanical problems in airplanes have not increased by 50 percent since last August
-->best answer. You can use the Assumption negative technique in Bible critical Power score: Mechanical problems in airplanes have increased by 50 percent since last August--> this turns out to be a weaken to the argument, so this is the best choice

(D) Airlines are less reluctant to report mechanical problems than they previously were
--> this seems alright, but not as strong as (C). The reluctance is just a weak and abstract reason to decide whether to report a mechanical problem. But because the frequency increase dramatically, 50%, so the reluctance seems to play no significant role

(E) Mechanical problems in airplanes have become easier to detect since last August
--> weaken

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by mrinal2100 » Thu Feb 25, 2010 9:18 am
how does the option c weaken the argument if we take the negation approach..if Mechanical problems in airplanes have increased by 50 percent since last August ,then the reports of airplane mechanical problems should also increase in frequency by 50 percent since last August...

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by tallazndood » Thu Feb 25, 2010 10:13 pm
mrinal2100 wrote:how does the option c weaken the argument if we take the negation approach..if Mechanical problems in airplanes have increased by 50 percent since last August ,then the reports of airplane mechanical problems should also increase in frequency by 50 percent since last August...
IMO: There're two likely situations that are causing the increase:

1. More mechanical problems that are previously NOT reported are now reported as a result of the more stringent rules.
2. There has been an increase in the number of mechanical problems since last August.

Conclusion ties the increase of 50% to Situation 1. Hence, it must be assuming that Situation 2 is NOT the case. Therefore, C is the right answer because the assumption is eliminating an alternative cause. By negating option C, it weakens the argument because Situation 2 could also be the cause of the increase (or Situation 1 is NOT necessarily the cause).

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by Testluv » Thu Feb 25, 2010 10:31 pm
This is another explain the phenomenon argument. The author is advancing an "accounting" for why reports of mechanical problems have increased. And his explanation--his account--is that the new rules are more stringent.

In other words:

the phenomenon: increase in number of reports of mechanical problems.

the author's explanation (conclusion): new (and more stringent) rules.

In all "explain the pheomenon" arguments, the author is assuming that there are no other explanations.

Choice C matches this prediction although rather than saying "no other explanations", it is specifically ruling out a clear competing explanation--that mechanical problems have in fact increased. Using the denial test: if mechanical problems HAVE incrased, then that would be the explanation for the greater number of reports of mechanical problems--not the more stringent rules.

Because, in the absence of choice C, the argument falls apart, the argument's reasoning depends on choice C; choice C is a necessary assumtion of the argument.
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by tanviet » Fri Mar 05, 2010 6:12 am
testluv, can I say that

in phenominon argumen

evidence is phenominon

coclusion is explanation

this is to quickly realize evidence and assumption.

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by Testluv » Fri Mar 05, 2010 12:04 pm
duongthang wrote:testluv, can I say that

in phenominon argumen

evidence is phenominon

coclusion is explanation

this is to quickly realize evidence and assumption.
yes, you can say that.
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by joseph32 » Sun May 15, 2016 11:53 pm
I believe the answer should be C