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Intern
Joined: 30 Aug 2015
Posts: 21
Given Kudos: 8
GMAT 1: 570 Q42 V27
GMAT 2: 680 Q50 V35
The westinghouse air brake, first demonstrated successfully in 1868
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Updated on: 11 Sep 2021, 05:43
Updated on: 11 Sep 2021, 05:43
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Difficulty:
25%
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Question Stats:
73% (01:33) correct
27%
(01:50)
wrong
based on 3077
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The westinghouse air brake, first demonstrated successfully in 1868, had been developed to such an extent by 1887 that a train of 50 freight cars traveling at 20 miles per hour could be brought to a standstill in the space of 171 feet, whereas before they required 5 hand breakers over a distance of 1,500 feet for such a train to be stopped.
(A) whereas before they required 5 hand breakers over a distance of 1,500 feet for such a train to be stopped.
(B) whereas previously 5 hand breakers operating over a distance of 1,500 feet had been required to stop such a train.
(C) but before stopping the train required 5 hand breakers operating over a distance of 1,500 feet.
(D) but previously they required 5 hand breakers over a distance of 1,500 feet stopping the train.
(E) but before stopping such a train required 5 hand breakers over a distance of 1,500 feet.
(A) whereas before they required 5 hand breakers over a distance of 1,500 feet for such a train to be stopped.
(B) whereas previously 5 hand breakers operating over a distance of 1,500 feet had been required to stop such a train.
(C) but before stopping the train required 5 hand breakers operating over a distance of 1,500 feet.
(D) but previously they required 5 hand breakers over a distance of 1,500 feet stopping the train.
(E) but before stopping such a train required 5 hand breakers over a distance of 1,500 feet.
Originally posted by inakihernandez on 29 Apr 2016, 07:59.
Last edited by Bunuel on 11 Sep 2021, 05:43, edited 1 time in total.
Last edited by Bunuel on 11 Sep 2021, 05:43, edited 1 time in total.
Edited the question.
Magoosh GMAT Instructor
Joined: 28 Dec 2011
Posts: 4490
Given Kudos: 130
Re: The westinghouse air brake, first demonstrated successfully in 1868
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29 Apr 2016, 15:45
29 Apr 2016, 15:45
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Expert Reply
inakihernandez
The westinghouse air brake, first demonstrated successfully in 1868, had been developed to such an extent by 1887 that a train of 50 freight cars traveling at 20 miles per hour could be brought to a standstill in the space of 171 feet, whereas before they required 5 hand breakers over a distance of 1,500 feet for such a train to be stopped.
(a) whereas before they required 5 hand breakers over a distance of 1,500 feet for such a train to be stopped.
(b) whereas previously 5 hand breakers operating over a distance of 1,500 feet had been required to stop such a train.
(c) but before stopping the train required 5 hand breakers operating over a distance of 1,500 feet.
(d) but previously they required 5 hand breakers over a distance of 1,500 feet stopping the train.
(e) but before stopping such a train required 5 hand breakers over a distance of 1,500 feet.
Dear inakihernandez,(a) whereas before they required 5 hand breakers over a distance of 1,500 feet for such a train to be stopped.
(b) whereas previously 5 hand breakers operating over a distance of 1,500 feet had been required to stop such a train.
(c) but before stopping the train required 5 hand breakers operating over a distance of 1,500 feet.
(d) but previously they required 5 hand breakers over a distance of 1,500 feet stopping the train.
(e) but before stopping such a train required 5 hand breakers over a distance of 1,500 feet.
My friend, I'm happy to respond.
Official GMAT SC questions are funny. Many times, the OA is a well-written gem, beautifully crafted, but sometimes the OA still has issues but it's the best of the bunch. I think this is such a question.
The opening "whereas" is a much more natural way to create the contrast that the writer is trying to create. The word "whereas" suggests contrast but it also implies a comparison, whereas the word "but" simply delineates a sharp change in the direction of the logic.
Choice (A) uses "they" to refer to the trains and then says "such a train"---this double reference is confusing.
Choice (B) has no pronoun issues, and it uses the "whereas," so it's best of this bunch. This is a rare official GMAT SC question in which I am embarrassed by the poor quality of the OA. It sounds as if the "5 hand breakers" are physically separated from one another over a distance of 1500 meet---that, of course, is not the intended meaning, but that's how it sounds. This entire sentence would have to be re-written to create complete clarity. So, this is a very-far-from-ideal question, but (B) stands out as head and shoulders above the rest, so in that sense, this question has a very clear answer.
Does this make sense?
Mike
Magoosh GMAT Instructor
Joined: 28 Dec 2011
Posts: 4490
Given Kudos: 130
Re: The westinghouse air brake, first demonstrated successfully in 1868
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16 May 2016, 11:44
16 May 2016, 11:44
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Expert Reply
HarisinghKhedar
Hi Mike,
Thanks for your explanation. I chose wrong option on practice test for the following reasons :
1. I couldn't split between 'whereas' and 'but'. I ignored because both show contrast to some extent. There are other officials problems in which the ans choices are split between words (or conjuctions) which convey the same meaning but may not fit in given context for one or other reason. Any safer approach to avoid such traps?
2. I rejected B because I couldn't rationalise whether past perfect is ok. If the question stem (Without dates/timeframes) demands sequencing of events in past, I still do better. But it gets tougher when the stem involves years/dates etc. I was confused for the same reason.
3. Before/previously - same reasons as 1.
Only thing I could properly use was - pronoun agreement which helped me to reject two choices at best.
Would appreciate your inputs.
Cheers
Dear HarisinghKhedar,Thanks for your explanation. I chose wrong option on practice test for the following reasons :
1. I couldn't split between 'whereas' and 'but'. I ignored because both show contrast to some extent. There are other officials problems in which the ans choices are split between words (or conjuctions) which convey the same meaning but may not fit in given context for one or other reason. Any safer approach to avoid such traps?
2. I rejected B because I couldn't rationalise whether past perfect is ok. If the question stem (Without dates/timeframes) demands sequencing of events in past, I still do better. But it gets tougher when the stem involves years/dates etc. I was confused for the same reason.
3. Before/previously - same reasons as 1.
Only thing I could properly use was - pronoun agreement which helped me to reject two choices at best.
Would appreciate your inputs.
Cheers
I'm happy to respond.
I will go through your numbers in reverse order. 3) On "before" vs. "previously," notice a subtle difference. The word "previously' is 100% an adverb and nothing but an adverb: its usage is perfectly unambiguous. By contrast, the word "before" can be used either as an adverb (as it is used in these answer choices in this problem) or as a subordinate conjunction or as a preposition.
He came to the house to visit me, but before, I had left to go to the store. = adverb use of "before"
Before he came to the house to visit me, I already had left to go to the store. = subordinate conjunction use of "before"
Before his arrival at the house looking for me, I already had left to go to the store = preposition use of "before"
In this problem, the word "before" is intended in its adverb usage, but it creates ambiguity because it could be understood as preposition:
(C) ... but, before stopping the train, [who?] required 5 hand breakers operating over a distance of 1,500 feet
That opening phrase "before stopping the train" is likely to be understood as a prepositional phrase, and when we get to the verb, we realize, "wait, we need a subject!" We have to go back and re-interpret the word "before" as a adverb and the gerund "stopping" as the subject. This is a very subtle point. Any piece of writing that creates the expectation of one sort of reading and then jarringly forces us to adapt another reading is rhetorically awkward. Good writing fulfills our grammatical expectations in a way that allows the meaning to unfold. That's a problem with "before" in this context.
2) For use of the past perfect, see this blog:
Past Perfect on GMAT Sentence Correction
You will notice that in the example sentence in #3, I used the past perfect, even though there were other indicators of the time sequence. I did so because I was trying to create emphasis: this is a justifiable use of the past perfect even when other elements of the sentence indicate the time sequence. Much in the same way, the sentence in this official SC question is creating this huge sense of contrast between after the air brake vs. before the air brake. The past perfect helps to underscore that logical and rhetorical contrast.
1) This is the hardest, especially for folks for whom English is not a native language---the subtle differences between closely related words. Here, "but" and "whereas" are both contrast words: that is there similarity. The difference lies in the connotation, the quality of the contrast. The word "but" is a 180-degree completely turn around. The word "whereas" is softer, suggesting comparison and connection as well as contrast. I don't know if you have an experience with improv theater: the word "but" is many ways is equivalent to a kind of "no," whereas the word "whereas" is more equivalent to "yes and" (in improv theaters, actors are told to avoid the word "but" and make use of "yes and," to keep the flow of the dialogue going).
How do you learn all these subtle distinctions and connotations? By reading. See:
How to Improve Your GMAT Verbal Score
It is impossible to arrive at GMAT SC mastery by assembling some complete list of differences in meaning. That is a left-brain fantasy that is entirely unworkable. The only way to develop the intuition for the language is to develop a rigorous habit of daily reading.
Does all this make sense?
Mike
