Reading skills among high school students in Gotham have

My thoughts:

Keyword is ONLY. i.e. Overcrowding is a necessary condition for decline in reading skills. Hence, conclusion is: If Decline, then Overcrowding.

E states: some non-overcrowded schools experience decline reading skills. It effectively means that if Decline then NOT necessarily overcrowding. Hence, weakens conclusion.

D simply says that there is no decline in reading skills for some overcrowded schools. It does nothing to the conclusion because the conclusion does not talk about the scenario when there is no decline in reading skills.

the conclusion says the overcrowd in the school is causing the decline in the reading skills.
To weaken this one, we have to show that the overcrowd is not the only reason for the decine in reading skills.

Now in D
Students' reading skills have not declined in other cities where the high schools are just as crowded as those of Gotham.
it says, there are other cities which are as crowded as Gotham, where the reading skills have not declined. But it doesn't give any information regarding the other reasons for the decline.

In E
Schools are not overcrowded in many cities where high school reading scores have declined more than they have in Gotham.
it says in some less crowded cities the reading skills have declined. So there has to some reason for this delcine other than the overcrowd. This one weakens the argument by introducing some other factors.

So E is the ans

E says !overcrowding => reading decline.
Meaning effect occurs even if cause does not.

Though I went with E but didnt like D and E both for the above highlighted portions that have nowhere been mentioned in the argument.

Great question!!!!

Weakening an argument by introducing an "alternate causation"...

D is close -- but subtle differences between schools and high schools, and between reading scores and reading scores among high school students...

E wins!

Pretty good explanations.

It is a cause + effect situation. To weaken it, you must "prove" otherwise in similar conditions (ex.: A place where the effect is present, i mean, the skills have also been constantly decreasing), but for any reason other than "overcrowded". It could even be a random X reason, as long as it is different than "overcrowded".

D is wrong because the effect was different.

Here is the difference between D and E:

D is saying that overcrowding did not cause a decrease in reading skills among some schools. If the conclusion was overcrowding ALWAYS causes a decrease in reading skills, then this answer would be correct. However, the conclusion is that overcrowding is the ONLY cause of a decline in reading skills. E states that there must be other causes for a decline in reading skills than overcrowding. This directly addresses the conclusion.

Thus E. It boils down to the difference between ONLY and ALWAYS.

Dude, could seem that what others cities do is out of scope. Doesn't have the answer to be a subset of the stimulus? In any other question this would be out of scope. ..

Here, The cause is overcrowding which has resulted into declining reading skills.

Hence, if we can identify that some other cause has given resulted in declining reading skills, we can weaken the argument.
Option B says that overcrowding is not associated with lower reading scores. Hence, something else is associated with it .

Please advise, what flaw is there in this reasoning.

clearly, all but D and E can easily be eliminated.
I chose E.
no cause -> effect still is present. thus, cause does not lead to effect.

Please clear my doubt

E says many cities but not all other cities, leaving a scope for some other cities similar to Gotham?

D says about all other schools that are just as crowded as Gotham, so narrowed down to the required comparison?

B says not always, meaning sometimes may be possible, same like E says ?

C is saying a different reason but that reason was not properly associated with the decline or incline in the scores, so can be skipped

A This adds no value

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E.

Because in causality weakeners, we need to find if effect is present even in the absence of the said cause. A, B and C are out.

D. Students' reading skills have not declined. So, they may have increased or remained constant in schools that are as crowded as Gotham is. Close contender. But we are more concerned about schools with declining reading skills of students. Hold but check the one remaining answer choice.

E. Clearly mentions that in "many" schools, the reading scores have "declined" even without "overcrowding". Goes in line with our pre-thinking. Correct.

Which is that next question mentioned in above solution-->(Note: This ties in perfectly with the logical element present in the next question.)

The tags mention both Kaplan and Veritas as a source... I take it this is a Kaplan question?

I don't think this is a good question

(E) says Schools are not overcrowded in many cities where high school reading scores have declined more than they have in Gotham.

Aren't we focusing on what happened in Gotham? Even though it may be true that overcrowding is not the cause in many cities, overcrowding can still be the cause in "Gotham".

Experts please chime in, thank you

Reading skills have declined.
Schools are overcrowded.

Conclusion: Overcrowding is necessary for decline in skills.
The use of the word "only" shows that the author considers "overcrowding" necessary for decline in reading skills. It is our "only if" construct.
Only if overcrowding, then decline in reading skills.

We need to weaken this i.e. we need to weaken that overcrowding is necessary for decline in reading skills.

a) The high school system in Gotham succeeds in giving students a good education at considerably less cost than do most systems.

Cost is irrelevant

b) Several cities have found that overcrowding in the schools is not always associated with lower reading scores.

Overcrowding may not always lead to lower reading scores. This says that overcrowding may not be sufficient. Our argument does not worry about sufficiency. We are concerned about necessity.

c) Gotham schools have a greater teacher-to-student ratio than most other school systems.

Teacher-student ratio is irrelevant. We are talking about overcrowding - too many students in one school. We don't know the parameters on which "too many" is measured.

d) Students' reading skills have not declined in other cities where the high schools are just as crowded as those of Gotham.

Same as option (B). Overcrowding is not sufficient to cause lower reading skills.

e) Schools are not overcrowded in many cities where high school reading scores have declined more than they have in Gotham.

Shows that without overcrowding too, decline in reading skills can occur. So overcrowding is not necessary. Weakens our argument.
Note that the author is applying the principle to Gotham. We need to weaken the principle. For that we can show how it doesn't apply necessarily and hence it may not apply to Gotham either.

Answer (E)

Note: I may have worded the argument differently to make it clearer.

Imo E
'Only' usage indicates that overcrowding is the necessary condition of declining scores. To weaken the conditional reasoning is to prove that overcrowding is not the necessary condition; declining scores can happen without overcrowding. E is correct.

B and D are not correct since they concern with sufficient condition of overcrowding

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