There are hopeful signs that

[RonPurewal]

Hi Could you help me explain why D is incorrect in this example?

take a look at the locations of modifiers -- you have "33 percent of the energy [no modifier] comes from nuclear power in germany".

the left-hand part of this construction -- "33 percent of the energy" -- seems to suggest that we're talking about the same energy as before, i.e., the energy in france. also, the latter part seems to suggest that the nuclear power itself, rather than the energy use, is in germany.
so, the literal meaning of that choice is that 33% of the french energy usage comes from nuclear power that is itself somehow located in germany. this is nonsense.

there's also the more accessible fact that the parallelism is far inferior to that in the correct choice.
in the correct choice, you have the expressions "75 percent of the energy produced in france" and "33 percent of the energy produced in germany", which are perfectly parallel; in choice (d), these things are written with much worse parallelism.

[divineacclivity]

* the air quality of las vegas was higher in 2007 than that in 1997
--> INCORRECT
this isn't parallel; the left-hand structure is interrupted by a verb, while the right-hand structure contains no such verb.

Ron,

Is the following sentence correct?
the air quality of las vegas was higher in 2007 than in 1997

thanks

[divineacclivity]

i could've sworn this problem was in another thread, but the search box won't find it.

there are two splits you should use to narrow down this problem:

(1) the second half of the construction 'ten times as much ... ____' is as, not than. therefore, you can eliminate answers (a) and (e), which contain 'than'. (i'm assuming that (e) is supposed to say 'than', not 'then'; i don't think the gmat problems would that blatant an error)

(2) the pronoun 'it' is inappropriate, because 'it' must refer to the ENTIRETY of the noun phrase serving as an antecedent.
for instance, the following is an improper sentence: last year's attendance was ten thousand greater than it was this year
in the above sentence, the pronoun 'it' must necessarily refer to last year's attendance, not just attendance.
the problem in this post has the same issue: the pronoun 'it' must refer to more than ten times as much energy, not just energy - an interpretation that makes no logical sense. therefore, all answer choices containing the pronoun 'it' are wrong.

if you don't like '...than was the case', you should learn to like it; this is one of those phrases that the gmat writers use to refer to concepts that don't fit under the usage constraints of traditional pronouns. (another popular one of these constructions is 'do so'.)

Would the following be good sentences grammatically:
1. More than 10 times as much energy is generated now as was generated in 1990
2. More than 10 times as much energy is generated now as was in 1990

[tim]

Is the following sentence correct?
the air quality of las vegas was higher in 2007 than in 1997

yes

[tim]

Would the following be good sentences grammatically:
1. More than 10 times as much energy is generated now as was generated in 1990
2. More than 10 times as much energy is generated now as was in 1990

i think 1 is correct; 2 is a little too unclear and ambiguous to be seen in a correct GMAT sentence..

[divineacclivity]

Would the following be good sentences grammatically:
1. More than 10 times as much energy is generated now as was generated in 1990
2. More than 10 times as much energy is generated now as was in 1990

i think 1 is correct; 2 is a little too unclear and ambiguous to be seen in a correct GMAT sentence..

cool thanks.

[tim]

no problem..

[ravimba]

There are hopeful signs that we are shifting away from our heavy reliance on fossil fuels: more than ten times as much energy is generated through wind power now than it was in 1990.

A) generated through wind power now than it was
B) generated through wind power now as it was
C) generated through wind power now as was the case
D) now generated through wind power as it was
E) now generated through wind power then was the case

In the 1980’s the rate of increase of the minority population of the United States was nearly twice as fast as the 1970’s.

(A) twice as fast as
(B) twice as fast as it was in
(C) twice what it was in
(D) two times faster than that of
(E) two times greater than


In the above two sentence, the In the 1st one IT should not be used because IT should refer to complete noun + essential modifiers where as it refers only Energy. Hence A,B,D are ruled out. and the answer choice C is correct
In the second sentence, the OA is C, in which IT is used to refer RATE OF INCREASE OF THE MINORITY POPULATION OF THE UNITED STATES.

How is 1st sentence different from 2nd sentence? Why the answer choice with pronoun IT is ruled out in 1st sentence whereas it is not ruled out in 2nd sentence?

Thanks
Ravi

[jlucero]

Take a look at the two sentences with the entire noun phrases plugged back in for the pronoun:

There are hopeful signs that we are shifting away from our heavy reliance on fossil fuels: (more than ten times as much energy) is generated through wind power now than more than ten times as much energy was in 1990.

In the 1980’s (the rate of increase of the minority population of the United States) was nearly twice what (the rate of increase of the minority population of the United States) was in the 1970’s.

The first sentence doesn't make sense but the second one does. This is because the affect of multiplying is either part of the noun phrase (as it is in 1) or outside of the noun phrase (as it is in 2).

[ghong14]

'It' must refer to the ENTIRETY of the noun phrase serving as an antecedent.

Ron, does this principle only apply to situations where it is used in a comparison such as the current example or it overall? If I say The computer clocked at 3.5ghz beat the previous record holder, making it the fastest machine on the market.

Is it referring to the computer or the computer that clocked at 3.ghz.

I think I am having a hard time defining the scope of the phrase of the antecedent. Where does the antecedent phrase start and stop. I know it should include the original structure.

[tim]

Either interpretation is fine because both are referring to exactly the same thing.

[ghong14]

Can you please specify what i the scope of the "it" that is referred. Would is it more than ten times as much energy. If that is the case does it usually include everything that is around the referent pronoun till the verb.

Similarly in this sentence. Would the it refer to owning and living in a freestanding house on its own land?

og-review-10th-sc-73-t1595.html

According to a recent poll, owning and living in a freestanding house on its own land is still a goal of a majority of young adults, like that of earlier generations.

[RonPurewal]

Can you please specify what i the scope of the "it" that is referred. Would is it more than ten times as much energy.

yes. that's why "it" is wrong.

Similarly in this sentence. Would the it refer to owning and living in a freestanding house on its own land?

again, yes.
(if this is not 100% obvious from the context, then you aren't thinking enough about what the sentence actually means.)

[bodhisattwabiswas]

* the air quality of las vegas in 2007 was higher than that in 1997
--> CORRECT
note the perfect parallelism
(the air quality of las vegas) (in 2007)
parallel to
(that) (in 1997)

* the air quality of las vegas was higher in 2007 than that in 1997
--> INCORRECT
this isn't parallel; the left-hand structure is interrupted by a verb, while the right-hand structure contains no such verb.

thanks for the excellent explanation...
So, if we preserve the left hand side of the 2nd sentence, how to fix the right hand side of it?
If we say --- "than the air quality of las vegas was in 2007", is it right? or any other/better way?

[RonPurewal]

* The air quality of Las Vegas was higher in 2007 than it was in 1997.
--> This version is correct, since "it" stands for "the air quality of Las Vegas".


You can also just write "The air quality of LV was higher in 2007 than in 1997."