Because the population is denser there and the automobile

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Good Day GMAT GURU

Because the population is denser there and the automobile is therefore inefficient as a means of transportation, a commuter rail system serving a given population is usually five times more efficient in a European city than it is in an American city.


a) serving a given population is usually five times more efficient in a European city than it is in an American city

b) serving a given population will usually be five times more efficient if it is placed in a European city instead of an American city

c) will usually be five times more efficient in a European city than one serving a comparable population in an American city

d) in a European city will usually be five times more efficient than will a system serving a comparable population in an American city

e) that is implemented in a European city will usually be five times more efficient than if it is implemented with a comparable population in an American city

i have done following analysis

option A:serving a given population is usually five times more efficient in a European city than it is in an American city---->italicized part not parallel

option B : serving a given population will usually be five times more efficient if it is placed in a European city instead of an American city--->more cannot go with instead

option C :will usually be five times more efficient in a European city than one serving a comparable population in an American city--->italicized part not parallel

option D:in a European city will usually be five times more efficient than will a system serving a comparable population in an American city-----parallel

option E :that is implemented in a European city will usually be five times more efficient than if it is implemented with a comparable population in an American city --->italicized part not parallel


the general idea that i have used in this question is that we can have either of the following 2 construction
construction 1: X more than Y ----->with X and Y being parallel
construction 2: more X than Y ----->with X and Y being parallel

kindly tell me if my analysis is correct
thanks and regards

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by GMATGuruNY » Sun Apr 13, 2014 4:56 am
aditya8062 wrote:Good Day GMAT GURU

Because the population is denser there and the automobile is therefore inefficient as a means of transportation, a commuter rail system serving a given population is usually five times more efficient in a European city than it is in an American city.

a) serving a given population is usually five times more efficient in a European city than it is in an American city

b) serving a given population will usually be five times more efficient if it is placed in a European city instead of an American city

c) will usually be five times more efficient in a European city than one serving a comparable population in an American city

d) in a European city will usually be five times more efficient than will a system serving a comparable population in an American city

e) that is implemented in a European city will usually be five times more efficient than if it is implemented with a comparable population in an American city
A much faster approach:

When an introductory modifier includes a pronoun without an antecedent, the referent should appear in the following clause AS EARLY AS POSSIBLE.
Here, the introductory because-modifier includes there, a pronoun without an antecedent.
The intended referent -- a European city -- appears earliest in answer choice D.
Since this answer choice is error-free, eliminate A, B, C and E.

The correct answer is D.
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by aditya8062 » Sun Apr 13, 2014 6:08 am
thanks for that valuable point
in the sentence:a commuter rail system serving a given population is usually five times more efficient in a European city than it is in an American city.
in one of ur posts u have said that "it" is making it appear as if we are talking about the same commuter rail to be serving in both European city and an American city .i agree that pronoun "it" refers to nouns along with the modifiers -->so in this case "it" must be referring to "a commuter rail system serving a given population"
by that extention the above sentence becomes :a commuter rail system serving a given population is usually five times more efficient in a European city than it [a commuter rail system serving a given population] is in an American city
my doubt is by this logic this sentence seems oki .kindly tell me as what am i missing

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by GMATGuruNY » Sun Apr 13, 2014 7:29 am
aditya8062 wrote:thanks for that valuable point
in the sentence:a commuter rail system serving a given population is usually five times more efficient in a European city than it is in an American city.
in one of ur posts u have said that "it" is making it appear as if we are talking about the same commuter rail to be serving in both European city and an American city .i agree that pronoun "it" refers to nouns along with the modifiers -->so in this case "it" must be referring to "a commuter rail system serving a given population"
by that extention the above sentence becomes :a commuter rail system serving a given population is usually five times more efficient in a European city than it [a commuter rail system serving a given population] is in an American city
my doubt is by this logic this sentence seems oki .kindly tell me as what am i missing
A commuter rail system serving a given population is usually five times more efficient in a European city than it is in an American city.

One example of a commuter rail system serving a given population is the commuter rail system serving the people of Paris.
To see why the sentence above doesn't work, let's replace the two subjects -- a commuter rail system serving a given population and it -- with the commuter rail system serving the people of Paris.
The following comparison is implied:
The commuter rail system serving the people of Paris is five times more efficient in a European city than is the commuter rail system serving the people of Paris in an American city.
The resulting comparison makes no sense.
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by dominhtri1995 » Mon Apr 14, 2014 5:34 am
Hi GuruNY
Can you explain what's wrong with (C)

Thanks

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by GMATGuruNY » Tue Apr 15, 2014 7:03 am
dominhtri1995 wrote:Hi GuruNY
Can you explain what's wrong with (C)

Thanks
In my first post above, I offered the easiest way to eliminate C.

Another reason is that C implies the following comparison:
A commuter rail system WILL USUALLY BE FIVE TIMES MORE EFFICIENT IN A EUROPEAN CITY than one serving a comparable population in an American city [WILL BE EFFICIENT IN A EUROPEAN CITY].
The words in brackets are omitted, but their presence is implied.
Not the intended meaning.
Last edited by GMATGuruNY on Tue Apr 15, 2014 3:48 pm, edited 1 time in total.
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by aditya8062 » Tue Apr 15, 2014 7:52 am
Another reason is that C implies the following comparison:
A commuter rail system WILL USUALLY BE FIVE TIMES MORE EFFICIENT IN A EUROPEAN CITY than one serving a comparable population in an American city {WILL BE EFFICIENT IN A EUROPEAN CITY].
considering the above quote can we make a generalization that in a construction "more .....than ....."
what ever appears in between "more" and "than" is implied after the "than" construction

thanks and regards

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by GMATGuruNY » Tue Apr 15, 2014 3:47 pm
aditya8062 wrote:
Another reason is that C implies the following comparison:
A commuter rail system WILL USUALLY BE FIVE TIMES MORE EFFICIENT IN A EUROPEAN CITY than one serving a comparable population in an American city {WILL BE EFFICIENT IN A EUROPEAN CITY].
considering the above quote can we make a generalization that in a construction "more .....than ....."
what ever appears in between "more" and "than" is implied after the "than" construction

thanks and regards
We can generalize as follows:
SUBJECT + VERB + more + X + than + SUBJECT.
In this construction, both the VERB and X are implied in the clause after than.

Carrots are more nutritious than cupcakes.
Conveyed meaning:
Carrots are more nutritious than cupcakes [are nutritious].

Adam ate more pizza than Bob.
Conveyed meaning:
John ate more pizza than Bob [ate pizza].
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by aditya8062 » Tue Apr 15, 2014 7:01 pm
thanks gmat guru
i totally get your point about this construction :SUBJECT + VERB + more + X + than + SUBJECT.
In this construction, both the VERB and X are implied in the clause after than.


but please tell me what if the construction after "than" already has a verb . in that case is the verb before "than" also implied after "than"?

also in a construction :SUBJECT + VERB + more + X + than + SUBJECT Y ,where Y is similar to X -->in this case is X also implied after "than"

thanks and regards

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by GMATGuruNY » Wed Apr 16, 2014 2:48 am
aditya8062 wrote:thanks gmat guru
i totally get your point about this construction :SUBJECT + VERB + more + X + than + SUBJECT.
In this construction, both the VERB and X are implied in the clause after than.


but please tell me what if the construction after "than" already has a verb . in that case is the verb before "than" also implied after "than"?
In general:
more X than Y serves to compare CLAUSES.
The first clause is composed of SUBJECT + VERB + OTHER STUFF.
The second clause is the same as the first, except for whatever new words appear after than.

If only a NEW SUBJECT appears after than, then implied in the second clause are the VERB and the OTHER STUFF from the first clause.
Carrots are more nutritious than cupcakes.
Conveyed meaning:
Carrots are more nutritious than cupcakes [are nutritious].

If only THE OTHER STUFF appears after than, then implied in the second clause are the SUBJECT AND VERB from the first clause.
Adam ate more carrots than cookies.
Conveyed meaning:
Adam ate more carrots than [Adam ate[ cookies.

If both a NEW SUBJECT and a NEW VERB appear after than, then only the OTHER STUFF is implied in the second clause.
Adam has written more books than Bob has read.
Conveyed meaning:
Adam has written more books than Bob has read [books].
also in a construction :SUBJECT + VERB + more + X + than + SUBJECT Y ,where Y is similar to X -->in this case is X also implied after "than"

thanks and regards
The nature of the subjects should not affect the general rule.
Can you provide an official example?
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by aditya8062 » Wed Apr 16, 2014 6:18 am
thanks gmat guru for this elaborate reply
but somewhere i feel that at times ellipsis tend to astonish me .
i agree with all your example but i feel that at times i find some exceptions
for instance :The people in New York are nicer than in Los Angeles.---->in this case "the people" is not implied
correct sentence wud have been :The people in New York are nicer than those in Los Angeles.

now in the sentence 2 :The people are nicer in New York than in Los Angeles.---> is ellipses understood in sentence 2 .also plz tell me if sentence 2 is correct

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by GMATGuruNY » Thu Apr 17, 2014 3:53 am
aditya8062 wrote:thanks gmat guru for this elaborate reply
but somewhere i feel that at times ellipsis tend to astonish me .
i agree with all your example but i feel that at times i find some exceptions
for instance :The people in New York are nicer than in Los Angeles.---->in this case "the people" is not implied
correct sentence wud have been :The people in New York are nicer than those in Los Angeles.

now in the sentence 2 :The people are nicer in New York than in Los Angeles.---> is ellipses understood in sentence 2 .also plz tell me if sentence 2 is correct
Lest we offend the good people of Los Angeles, let's change the subject matter.

Incorrect: The books on the bottom shelf are less expensive than on the top shelf.
Here -- because the second clause lacks an explicit subject -- both clauses seem to be about the books on the bottom shelf.
The result is a nonsensical comparison:
The books on the bottom shelf are less expensive than [the books on the bottom shelf] on the top shelf [are expensive].
To make it clear that the second clause is about a DIFFERENT set of books, the second clause requires ITS OWN SUBJECT:
The books on the bottom shelf are less expensive than THOSE on the top shelf.
Conveyed meaning:
The books on the bottom shelf are less expensive than those on the top shelf [are expensive].

The books are less expensive on the bottom shelf than on the top shelf.
Here, on the bottom shelf seems to serve as an adverb modifying less expensive, indicating WHY the books are less expensive.
The implication is that being on the bottom shelf CAUSES the books to be less expensive.
Not the intended meaning.
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by RBBmba@2014 » Mon Apr 13, 2015 9:18 am
Because the population is denser there and the automobile is therefore inefficient as a means of transportation, a commuter rail system serving a given population is usually five times more efficient in a European city than it is in an American city.

a) serving a given population is usually five times more efficient in a European city than it is in an American city

@ Mitch - confused with this part of option A.

Why "it " can't refer to the 'commuter rail system ' ONLY instead of referring to 'commuter rail system serving a given population' as a whole ?

P.S: PLEASE NOTE that I don't have any concern in understanding why A is incorrect (re the antecedent issue of the introductory modifier of 'Because-clause') , just would like to clarify the above aspect.

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by RBBmba@2014 » Wed Jun 03, 2015 7:26 am
RBBmba@2014 wrote:Because the population is denser there and the automobile is therefore inefficient as a means of transportation, a commuter rail system serving a given population is usually five times more efficient in a European city than it is in an American city.

a) serving a given population is usually five times more efficient in a European city than it is in an American city

@ Mitch - confused with this part of option A.

Why "it " can't refer to the 'commuter rail system ' ONLY instead of referring to 'commuter rail system serving a given population' as a whole ?

P.S: PLEASE NOTE that I don't have any concern in understanding why A is incorrect (re the antecedent issue of the introductory modifier of 'Because-clause') , just would like to clarify the above aspect.
Hi Mitch - can you pleas shed light on the above concern ?

Also, re choice C - if this were the sentence ONLY on its own, then would it be wrong as far as COMPARISON is concerned in GMAT ?

"A commuter rail system will usually be five times more efficient in a European city than one (=a commuter rail system) serving a comparable population in an American city (WILL BE) " ?

(Without considering the 'Because-clause' here just to understand the COMPARISON as a standalone)

Look forward to hear your feedback.Much thanks in advance.

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by RBBmba@2014 » Fri Jun 05, 2015 3:48 am
Mitch - any thoughts on the IMMEDIATE above post ?