Sentence Correction

Laboratory rats and mice live up to 40 percent longer than usual when fed a diet of at least 30 percent fewer calories than that which they would normally eat, but that otherwise contains all necessary vitamins and nutrients.

a. of at least 30 percent fewer calories than that which they would normally eat, but that otherwise
b. with at least 30 percent fewer calories than what they would normally eat though otherwise it
c. that has at least 30 percent fewer of the calories that they would normally eat, but otherwise it
d. that has at least 30 percent fewer calories than they would normally eat but that otherwise
e. that has at least 30 percent fewer calories than that which they would normally eat, though that otherwise

I have been reading the explanations for about 15-20 minutes but still I am not able to understand why the comparison is not correct in choice A&E.

Rats and mice live longer when fed a diet that has at least 30 percent fewer calories than that which they would normally eat.

Aren't we comparing diet that has <30% calories with diet which they normally eat

Someone please explain.

Laboratory rats and mice live up to 40 percent longer than usual when fed a diet that has at least 30 percent fewer calories than they would normally eat but that otherwise contains all necessary vitamins and nutrients.

I am trying to understand the sentence structure. Please correct me if I am wrong.

Laboratory rats and mice live up to 40 percent longer than usual when fed a diet that X but that Y.
X = has at least 30 percent fewer calories than they would normally eat
Y = otherwise contains all necessary vitamins and nutrients.
In X again there is a comparison stating diet has 30% fewer calories than they would normally eat.

Is it correct ? Please help.

@alexcey
"Diet A has 30 percent fewer calories than diet B."

here Sentence is correct but the comparison is not correct. I means here you are comparing THE DIET to THE CALORIES, whereas the actual comparison should be between the CALORIES IN DIET A vs CALORIES IN DIET B which can be shown in the following sentence :

"Diet A has 30 percent fewer calories than Diet B has."

what are the 2 parallel elements in this sentence: Laboratory rats and mice live up to 40 percent longer than usual.

i think that parallelism is ellipse-ed and full sentence would be "Laboratory rats and mice live up to 40 percent longer than they live usually". However, only thing that i am worried about is that in my 2nd sentence "usual" is changed to "usually" and ellipsis do not incorporate any change of words.

GMATGuruNY wrote:

fangtray wrote:Laboratory rats and mice live up to 40 percent longer than usual when fed a diet of at least 30 percent fewer calories than that which they would normally eat, but that otherwise contains all necessary vitamins and nutrients.

a. of at least 30 percent fewer calories than that which they would normally eat, but that otherwise
b. with at least 30 percent fewer calories than what they would normally eat though otherwise it
c. that has at least 30 percent fewer of the calories that they would normally eat, but otherwise it
d. that has at least 30 percent fewer calories than they would normally eat but that otherwise
e. that has at least 30 percent fewer calories than that which they would normally eat, though that otherwise

Could an expert help me with why "than that which" ..."but that" is wrong?

I received a PM requesting that I comment.

A and E:
than THAT which they would normally eat
a diet...THAT otherwise contains all necessary nutrients
The first that refers to the DIET NORMALLY EATEN BY RATS.
The second that refers to the DIET THAT HAS FEWER CALORIES but otherwise contains all necessary nutrients.
Within the context of a single modifier, the same pronoun -- THAT -- cannot serve to replace two different referents (the two different diets).
Eliminate A and E.

B: Laboratory rats live longer when fed a diet...though otherwise it contains all necessary nutrients.
C: Laboratory rats live longer when fed a diet...but otherwise it contains all necessary nutrients.
These options seem to imply the following contrast:
Laboratory rats live longer, EVEN THOUGH their diet contains all necessary nutrients.
Not the intention.
The intended meaning is as follows:
Laboratory rats live longer when fed a diet THAT contains all necessary nutrients.
Eliminate B and C.

The correct answer is D.

Hi GmatGuru,

Thanks for your explanation to this question. I totally understand your explanation but i seek few clarifications here.

After Inserting the correct answer choice to the question,the sentence reads as follows

Laboratory rats and mice live up to 40% longer than usual when fed a diet that has at least 30% fewer calories than they would normally eat but that otherwise contains all necessary vitamins and nutrients


I understand that if we use "that" after "fewer than" then it will be referring to the diet that has at least 30% fewer calories and will read as below.

Laboratory rats and mice live up to 40% longer than usual when fed a diet that has at least 30% fewer calories than that(diet that has at least 30% fewer calories) they would normally eat but that otherwise contains all necessary vitamins and nutrients.

This doesn't make sense,but if we use for example,"the one" instead of that it would read as follows

Laboratory rats and mice live up to 40% longer than usual when fed a diet that has at least 30% fewer calories than the one they would normally eat but that otherwise contains all necessary vitamins and nutrients.

my question is whether this version will be grammatically and logically correct?

if my understanding is right the sentence is ultimately trying to convey the below meaning.

Laboratory rats and mice live up to 40% longer than usual when fed a diet that has at least 30% fewer calories than (the diet) they would normally eat but that otherwise contains all necessary vitamins and nutrients.

but if we can't use "that" in place of "the diet" shall we not use something else such as "the one". if we don't use a place holder will that be correct and will "the diet" is automatically understood in that case? Please clarify.


it will also be of great help if you can clarify the below official explanations to the wrong answer choices of this question.

A)The sentence awkwardly describes a diet of calories;
the singular pronoun that logically refers to diet but syntactically is compared with the plural calories.

I understand the first part but i am not able to understand the part "singular pronoun "that" is syntactically compared with the plural calories". My question is how?

E)The singular relative pronoun that nonsensically refers to the plural calories,and the second appearance of that is without a referent.

In this explanation also the part where it says "The singular relative pronoun that nonsensically refers to the plural calories". As far as i understand that relative pronoun may refer to plural nouns. if my understanding is correct then why in the explanation above "that" is defined as singular relative pronoun.


I hope i have made my queries clear. it will be really helpful for a lot of people,including me if you can clarify these queries in detail.

Thanks,

gmatguru,
what are the other errors in B ? are there any grammatical errors in B ?

gmatguru,
any update on the above ?

thank you!

ngk4mba3236 wrote:gmatguru,
what are the other errors in B ? are there any grammatical errors in B ?

OA: a diet that has fewer calories than they would normally eat
Conveyed comparison:
a diet that that has fewer calories than they would normally eat [calories]
Here, how many calories the diet has is logically compared to how many calories the rats would normally eat.

B: a diet that has fewer calories than what they would normally eat
Here, a DIET is illogically compared to WHAT THEY WOULD NORMALLY EAT, implying that what they would normally eat is NOT a diet.
Not the intended meaning.
Eliminate B.

GMATGuruNY wrote: B: fewer calories than what they normally would eat
Conveyed comparison:
calories that are fewer than what they normally would eat
It is illogical to compare CALORIES to WHAT THEY NORMALLY WOULD EAT.
Eliminate B.

gmatguru,
didn't get this!

why the phrase "WHAT THEY NORMALLY WOULD EAT" doesn't mean the calories [=WHAT] they normally would eat ?

GMATGuruNY wrote: OA: a diet that has fewer calories than [the calories] they would normally eat
Here, the words in brackets are omitted, but their presence is implied.

Hi Mitch, I am finding it difficult to comprehend that the sentence is suggesting that rats eat calories.

To me, it seems that we eat diet and the diet in turn, has calories.

Hence, also wanted to check with you if we can interpret option D as:

diet that has at least 30 percent fewer calories than they would normally eat (has calories)

Basically, "they would normally eat" refers to "diet" and not "calories". This way, we are comparing:
i) One diet (that has at least 30% fewer calories)
ii) Other diet (their normal diet that has normal calories)

Would appreciate your comments, as always.