shift work equation

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shift work equation

by inactived » Sat Sep 11, 2010 1:48 am
Source: #134, Official Guide 11th.

Recently implemented "shift-work equations" based
on studies of the human sleep cycle have reduced
sickness, sleeping on the job, fatigue among shift
workers, and have raised production efficiency in
various industries.

(A) fatigue among shift workers, and have raised
(B) fatigue among shift workers, and raised
(C) and fatigue among shift workers while raising
(D) lowered fatigue among shift workers, and raised
(E) and fatigue among shift workers was lowered
while raising

This question is explained quite clear in this post (https://www.beatthegmat.com/large-drop-i ... t6457.html), however, I have yet not understood the parallel structure as following:

- Why is "while raising" in choice C possible observed as parallel to "have reduced"? Isn't it supposed to be "while have been raising" or "while have raised"?

Tks
Source: — Sentence Correction |

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by GMATGuruNY » Sat Sep 11, 2010 4:05 am
inactived wrote:Source: #134, Official Guide 11th.

Recently implemented "shift-work equations" based
on studies of the human sleep cycle have reduced
sickness, sleeping on the job, fatigue among shift
workers, and have raised production efficiency in
various industries.

(A) fatigue among shift workers, and have raised
(B) fatigue among shift workers, and raised
(C) and fatigue among shift workers while raising
(D) lowered fatigue among shift workers, and raised
(E) and fatigue among shift workers was lowered
while raising

This question is explained quite clear in this post (https://www.beatthegmat.com/large-drop-i ... t6457.html), however, I have yet not understood the parallel structure as following:

- Why is "while raising" in choice C possible observed as parallel to "have reduced"? Isn't it supposed to be "while have been raising" or "while have raised"?

Tks
Quickest approach:

Notice that C and E begin with the conjunction and; A, B and D do not. Since the shift-work equations have reduced a list of three things -- sickness, sleeping on the job, and fatigue -- the conjunction and is needed before the last item in the list (fatigue). Eliminate A, B and D.

In, E lowered creates an error of redundancy with reduced. Eliminate E.

The correct answer is C.

One take-away:

When you see connecting words such as and, but, or, etc. changing in the answers, ask yourself:

Is the right connecting word being used?
Is the connecting word in the right place?


By noticing the placement of the word and in the SC above, we were able to eliminate three answer choices very quickly.

The phrase while raising in an adverbial modifier. An adverbial modifier does not have to be parallel with what it's modifying. In C, the following construction is correct:

The equations have reduced sickness...while raising efficiency.

Hope this helps!
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