In order to conserve the energy and heat they need to spend

Question

In order to conserve the energy and heat they need to spend the entire winter sitting motionless over incubating eggs, male emperor penguins huddle over the nests in groups, thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for isolated birds.

(A) thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for
(B) thereby reducing their rate of burning energy until it is 25 percent lower when compared with
(C) and they thereby reduce by 25 percent the rate they burn energy, as compared to what it would be with
(D) which thereby reduces by 25 percent their rate of burning energy, when comparing them to
(E) which thereby reduces the rate they burn energy so that it is 25 percent lower than

What I want to know is where in the world is thereby discussed in any grammar book?!?!

swanidhi · Accepted Answer

In order to conserve the energy and heat they need to spend the entire winter sitting motionless over incubating eggs, male emperor penguins huddle over the nests in groups, thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for isolated birds.

A)thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for
B)thereby reducing their rate of burning energy until it is 25 percent lower when compared with
C)and they thereby reduce by 25 percent the rate they burn energy, as compared to what it would be with
D)which thereby reduces by 25 percent their rate of burning energy, when comparing them to
E)which thereby reduces the rate they burn energy so that it is 25 percent lower than

Lets eliminate to get closer to the correct answer. My thought process would be something like -

To conserve something and something.. penguins huddle in groups....(incomplete) -->

I see these patterns -
reduce, reducing, than, compare

Now to minimize time its better to look at those options first which have a higher probability of being correct. Once we feel that its right, we'll try to find errors in other options to support our choice.
A B C D E
:idea:

than is better than using compare. A and E have it. In E which points to groups. Strike off E. A looks fine. Keep A.
A B C D E
We are left with B, C and D. Compared to is wrong idiom here. Compared with is correct.
:idea:

Remember, we use compare with for similar things and compare to for unlike things.
C and D are off the ring. C is a disaster if spend some more reading it.
A B ~~C D E~~
Best choices A and B so far. Usage of than is better than compare. Its more concise. Probability of A being correct answer looks higher. Select the option A, and read B again before confirming.
Wait a min, B is comparing apples to oranges. burnt energy 25% lower than isolated birds? A is the winner! :twisted:

A ~~B C D E~~

+Kudos if this helped!! :-D

than is better than using compare. A and E have it. In E which points to groups. Strike off E. A looks fine. Keep A. A B C D E We are left with B, C and D. Compared to is wrong idiom here. Compared with is correct. :idea:

Remember, we use compare with for similar things and compare to for unlike things. C and D are off the ring. C is a disaster if spend some more reading it. A B C D E Best choices A and B so far. Usage of than is better than compare. Its more concise. Probability of A being correct answer looks higher. Select the option A, and read B again before confirming. Wait a min, B is comparing apples to oranges. burnt energy 25% lower than isolated birds? A is the winner! :twisted:

A B C D E +Kudos if this helped!! :-D

mailnavin1 · Answer

Sorry I don't understand your q? y reasoning below

In order to conserve the energy and heat they need to spend the entire winter sitting motionless over incubating eggs, male emperor penguins huddle over the nests in groups, thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for isolated birds.

A)thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for
B)thereby reducing their rate of burning energy until it is 25 percent lower when  compared with isolated birds  wrong comparison
C)and they thereby reduce by 25 percent the rate they burn energy,  as compared to  what it would be  with 
D)which thereby reduces by 25 percent their rate of burning energy, when comparing them to  Same as B wrong comparison 
E)which thereby reduces the rate they burn energy so that it is 25 percent lower than  Same as B wrong comparison

hfbamafan · Answer

Sorry I just got confused starting a clause in a comparison by "thereby"

mun23 · Answer

In order to conserve the energy and heat they need to spend the entire winter sitting motionless over incubating eggs, male emperor penguins huddle over the nests in groups, thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for isolated birds.

A)thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for
B)thereby reducing their rate of burning energy until it is 25 percent lower when compared with
C)and they thereby reduce by 25 percent the rate they burn energy, as compared to what it would be with
D)which thereby reduces by 25 percent their rate of burning energy, when comparing them to
E)which thereby reduces the rate they burn energy so that it is 25 percent lower than

Need detail explanation of every answer option

aditya8062 · Answer

TO MUN23
though i picked A but i somehow don't like the question and i doubt if the correct option A is correct . i feel that A is run on .honestly i picked A only on the basis of comparison for only in A comparison is good

i will tell u why A is seeming to me as run on

In order to conserve the energy and heat they need to spend the entire winter sitting motionless over incubating eggs, male emperor penguins huddle over the nests in groups, thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for isolated birds.

the two portion that i have marked ,one in bold and the other one in italics ,are two independent clauses joined by comma

plz cite the source

mun23 · Answer

whats the difference between thereby reducing and they thereby reduce?

mun23 · Answer

Hi aditya
source is gmat prep question pack

vigneshceg · Answer

Mun,
Always ask yourself one question . Whether the result is caused by the subject or the action did by the subject. Here emperor penguins did not reduce the rate . It is the huddling act that did the rate reduction.

With this options C, D, & E are ruled out.

In option B it is given as their rate which is wrong.

Option A) is right.

doe007 · Answer

All duplicate threads on this topic have been merged.

Please check and follow the  Guidelines for Posting in Verbal GMAT forum  before posting anything.

PiyushK · Answer

In order to conserve the energy and heat they need to spend the entire winter sitting motionless over incubating eggs, male emperor penguins huddle over the nests in groups, thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for isolated birds.

A)thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for  -- Correct, but I do not like use of so that in this context I would prefer such that instead. I feel Penguins dont know how much percentage energy they will save they just do so because they feel good. 
B)thereby reducing their rate of burning energy until it is 25 percent lower when compared with  -- when compared is not right. 
C)and they thereby reduce by 25 percent the rate they burn energy, as compared to what it would be with  -- winner of most awkward gmat prep options. 
D)which thereby reduces by 25 percent their rate of burning energy, when comparing them to  -- nearest nouns are nests or groups plural -- but verb reduces is singular  
E)which thereby reduces the rate they burn energy so that it is 25 percent lower than  -- same as D.

tinni123 · Answer

In option B I believe lower when compared to is wrong , it should always be a than with lower.

Psiva00734 · Answer

In option D and E , which is modifes groups . it is incorrect.

In option C" and "coordinate conjunction used. 
it must be used two combine two independent clauses but not for modifier before.
would be for is idiomatic , would be with is unidiomatic.

In option B lower used but not followed by than.

It is one of the key marker if we want take away in sentence correction such as lower, greater,more, taller and higher must
followed by than most no of times.

If we see some other compartives , for instance, superior, inferior , exterior and interior should follow with preposition "to."

Apart form this , we use compared to for similar items. compared with for two different items.
so it is also wrong in B.

So option A is correct.

swanidhi · Answer

This is incorrect. Its the other way around. compare with - similar things compare to - unlike things +Kudos if this helped

Arjunarocks · Answer

A)thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for - correct
B)thereby reducing their rate of burning energy until it is 25 percent lower when compared with - lower and compared- redundant
C)and they thereby reduce by 25 percent the rate they burn energy, as compared to what it would be with - wrong comparison due to use of with
D)which thereby reduces by 25 percent their rate of burning energy, when comparing them to - them cant refer to rate
E)which thereby reduces the rate they burn energy so that it is 25 percent lower than - rate compared with birds

hawkeye1234 · Answer

Your Explanation for B is wrong.lower and compared are not redundant at all.The problematic thing is the referrant for "their" which could be nests too.plus "compared with isolated birds"is problematic.The rates should be compared.We cant compare rate of burning energy with isolated birds.

Arjunarocks · Answer

Thanks for your input Hawkeye!

aceGMAT21 · Answer

(A) thereby reducing the rate at which they burn energy so that it is 25 percent lower than it would be for 
 CORRECT. The  cause effect relationship  is also well maintained. 
so that here implies -- "with the result that"
What does "it" refers to here?? it refers to "the rate"

(B) thereby reducing their rate of burning energy until it is 25 percent  lower when compared with  
  lower  should be followed by  than  AND not  when compared with 
'the rate at which they burn energy' is better than 'their rate of burning energy'
also, wrong comparison at the end, rate is compared with the isolated birds
Usage of "until" does not seem logical!

(C) and they thereby reduce by 25 percent the rate they burn energy, as compared to what it would be with 
 wordy choice. Also, the intended meaning is lost by USING "AND" as now the CAUSE and EFFECT relation is lost. INCORRECT.
 as compared to what it would be with --  extremely wordy
WHAT does "it" refers to here? its "the rate" again.

(D) which thereby reduces by 25 percent their rate of burning energy, when  comparing  them to 
 usage of "which" is INCORRECT as it is referring to "groups"
who is comparing them to? not logical
also, wrong comparison at the end, rate is compared with the isolated birds

(E) which thereby reduces  the rate they burn energy  so that it is 25 percent lower than 
 usage of "which" is INCORRECT as it is referring to "groups"
also, wrong comparison at the end, male emperor penguins are compared with the isolated birds -- this is not the intended comparison!

POINT TO NOTE what "which" is referring to in options D and E:  
 In order to conserve the energy and heat they need to spend the entire winter sitting motionless over incubating eggs,  male emperor penguins huddle  over the nests  in groups ,  which thereby reduces  the rate they burn energy  so that it is 25 percent lower than  isolated birds.

Here, emperor penguins huddle in groups, "in groups" is referring back to the verb huddle. So, "which" here can refer to "groups" only and nothing else.

gamer23 · Answer

VeritasKarishma   egmat   GMATNinja  please help with option A,B, and C why B and C and C are incorrect

KarishmaB · Answer

The obvious big errors in (B) and (C):

(B) ... thereby reducing their rate of burning energy until it is 25 percent lower when compared with isolated birds.

Here, "rate of burning energy" is 25% lower when compared with birds. The comparison is illogical. The rate is 25% lower than it (the rate) would be for isolated birds.

(C) ... and they thereby reduce by 25 percent the rate they burn energy, as compared to what it would be with

"the rate they burn energy" is incorrect. It must be "the rate at which they burn energy". They burn energy at that rate. 
Also, the use of 'with' here implies the rate with birds which is illogical. It is the rate for birds.

In order to conserve the energy and heat they need to spend

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In order to conserve the energy and heat they need to spend

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