GMATGuruNY wrote:

TheGraduate wrote:C: Today's technology allows manufacturers to make small cars that are more fuel-efficient than those at any other time in production history.

D: Today's technology allows manufacturers to make more fuel-efficient small cars than those at any other time in their production history.

Apart from other errors,
in D those is not essential to the construction while in C those is essential. Is that right?

This line of reasoning is valid.

Incorrect: The manufacturer produced more cars this year than those last year.
Correct: The manufacturer produced more cars this year than last year.
The correct version implies the following comparison:
The manufacturer produced more cars this year than [it produced cars] last year.

Dear Mitch,

What does the incorrect version of your example above imply?

TheGraduate wrote:Today's technology allows manufacturers to make small cars more fuel-efficient now than at any time in their production history.
A) small cars more fuel-efficient now than at any time in their
B) small cars that are more fuel-efficient than they were at any time in their
D) more fuel-efficient small cars than those at any other time in their

Please comment on pronoun ambiguity of "their" in (A),(D) and of "they" and "their" in (B).

In A and D, it is unclear whether their serves to refer to manufacturers or to small cars.
Eliminate A and D.

Forms of they (they, them, their) cannot serve to compare TWO DIFFERENT SETS OF X.
Incorrect: This year's cellphones are better than THEY were last year.
Here, the usage of they implies that the SAME set of cellphones is being discussed in each instance.
Not so.
The intention is to compare ONE set of cellphones (this year's cellphones) to ANOTHER set of cellphones (last year's cellphones).
Correct: This year's cellphones are better than last year's.

B: small cars that are more fuel-efficient than they were at any time in their history
Here, the intention is compare ONE set of cars (today's small cars) to ANOTHER set of cars (small cars produced in the past).
Since forms of they cannot serve to compare two different sets of X, eliminate B.

GMATGuruNY wrote:

TheGraduate wrote:Today's technology allows manufacturers to make small cars more fuel-efficient now than at any time in their production history.
A) small cars more fuel-efficient now than at any time in their
B) small cars that are more fuel-efficient than they were at any time in their
D) more fuel-efficient small cars than those at any other time in their

Please comment on pronoun ambiguity of "their" in (A),(D) and of "they" and "their" in (B).

In A and D, it is unclear whether their serves to refer to manufacturers or to small cars.
Eliminate A and D.

Forms of they (they, them, their) cannot serve to compare TWO DIFFERENT SETS OF X.
Incorrect: This year's cellphones are better than THEY were last year.
Here, the usage of they implies that the SAME set of cellphones is being discussed in each instance.
Not so.
The intention is to compare ONE set of cellphones (this year's cellphones) to ANOTHER set of cellphones (last year's cellphones).
Correct: This year's cellphones are better than last year's.

B: small cars that are more fuel-efficient than at any time in their history
Here, the intention is compare ONE set of cars (today's small cars) to ANOTHER set of cars (small cars produced in the past).
Since forms of they cannot serve to compare two different sets of X, eliminate B.

You forget the 'they were' as appeared in the choice B above.

Mo2men wrote:

B: small cars that are more fuel-efficient than at any time in their history
Here, the intention is compare ONE set of cars (today's small cars) to ANOTHER set of cars (small cars produced in the past).
Since forms of they cannot serve to compare two different sets of X, eliminate B.

You forget the 'they were' as appeared in the choice B above.

Good catch.
I've edited my response accordingly.

Hi,
Can anyone please shed light on the SOURCE of this SC ?

@Sorin/BTG: Can we NOT make it mandatory to mention the SOURCE while posting any Verbal Or Quant Qs in the forum ?

This question is from the GMATPrep default exam pack.

Mo2men wrote:

Incorrect: The manufacturer produced more cars this year than those last year.

Dear Mitch,

What does the incorrect version of your example above imply?

It seems to imply the following nonsensical comparison:
The manufacturer produced more cars this year than cars last year produced.

GMATGuruNY wrote:

Mo2men wrote:

Incorrect: The manufacturer produced more cars this year than those last year.

Dear Mitch,

What does the incorrect version of your example above imply?

It seems to imply the following nonsensical comparison:
The manufacturer produced more cars this year than cars last year produced.

Thanks GMATGuru,

Another two questions:

1- Can this version be correct?

The manufacturer produced more cars this year than those last year by American manufacturers.

2- In the correct version:
The manufacturer produced more cars this year than last year.

The subject & verb are omitted but their presence are implied. However, can I omit the subject only and leave the verb? Is this ever a correct construction? Or should be both subject & verb omitted together or both appear together?
My proposed version: The manufacturer produced more cars this year than produced last year.

Mo2men wrote:Thanks GMATGuru,

Another two questions:

1- Can this version be correct?

The manufacturer produced more cars this year than those last year by American manufacturers.

This sentence is not viable.
In the second clause the omitted verb seems to be were produced (passive), while the verb in the first clause is produced (active).
An omitted verb may not be in a different voice from that of the antecedent verb.

However, can I omit the subject only and leave the verb? Is this ever a correct construction? Or should be both subject & verb omitted together or both appear together?
My proposed version: The manufacturer produced more cars this year than produced last year.

This sentence is not viable.
Generally, if the second clause in a comparison includes a verb, then the subject in the second clause may not be omitted.
It is quite common, however, for the second clause in a comparison to include a subject but omit the verb.
Country X produced more cars than Country Y.
Here, the clause in blue includes a subject (Country Y) but no verb.
Implied comparison:
Country X produced more cars than Country Y [produced].
The verb in brackets is omitted but implied.

GMATGuruNY wrote:It is quite common, however, for the second clause in a comparison to include a subject but omit the verb.
Country X produced more cars than Country Y.
Here, the clause in blue includes a subject (Country Y) but no verb.
Implied comparison:
Country X produced more cars than Country Y [produced].
The verb in brackets is omitted but implied.

In the example above, is verb 'produce' mandatory to allow a construction free of ambiguity? Take this example:

I love more pizza than Marry (does/loves).

I eat more pizza than Marry (does/eats).

In second example above, the meaning could help us to eliminate verb in second clause. But does GMAT accept this omission depending on meaning?

Thanks Sir

gmattoend wrote:

GMATGuruNY wrote:It is quite common, however, for the second clause in a comparison to include a subject but omit the verb.
Country X produced more cars than Country Y.
Here, the clause in blue includes a subject (Country Y) but no verb.
Implied comparison:
Country X produced more cars than Country Y [produced].
The verb in brackets is omitted but implied.

In the example above, is verb 'produce' mandatory to allow a construction free of ambiguity? Take this example:

I love more pizza than Marry (does/loves).

I eat more pizza than Marry (does/eats).

In second example above, the meaning could help us to eliminate verb in second clause. But does GMAT accept this omission depending on meaning?

Thanks Sir

The verb in the second clause may be omitted as long as the intended comparison is crystal clear.
Correct:
John ate more pizza than Mary.
Here, only interpretation is possible:
John ate more pizza than Mary ate.
Since the intended comparison is crystal clear, a verb is not required in the second clause.

Not viable:
Russia exports more oil to Europe than the United States.
Here, the intended comparison is NOT crystal clear.
Two possible meanings:
Case 1: Russia exports more oil to Europe than IT EXPORTS OIL TO THE UNITED STATES.
Case 2: Russia exports more oil to Europe than THE UNITED STATES EXPORTS OIL TO EUROPE.
If Case 2 is intended, a verb is required in the second clause to make the intended comparison crystal clear.
Correct:
China exports more oil to Europe than DOES the United States.

GMATGuruNY wrote:

TheGraduate wrote:Today's technology allows manufacturers to make small cars more fuel-efficient now than at any time in their production history.
A) small cars more fuel-efficient now than at any time in their
B) small cars that are more fuel-efficient than they were at any time in their
D) more fuel-efficient small cars than those at any other time in their

Please comment on pronoun ambiguity of "their" in (A),(D) and of "they" and "their" in (B).

In A and D, it is unclear whether their serves to refer to manufacturers or to small cars.
Eliminate A and D.

Forms of they (they, them, their) cannot serve to compare TWO DIFFERENT SETS OF X.
Incorrect: This year's cellphones are better than THEY were last year.
Here, the usage of they implies that the SAME set of cellphones is being discussed in each instance.
Not so.
The intention is to compare ONE set of cellphones (this year's cellphones) to ANOTHER set of cellphones (last year's cellphones).
Correct: This year's cellphones are better than last year's.

B: small cars that are more fuel-efficient than they were at any time in their history
Here, the intention is compare ONE set of cars (today's small cars) to ANOTHER set of cars (small cars produced in the past).
Since forms of they cannot serve to compare two different sets of X, eliminate B.

Dear GMATGuru,

In the OA C, does 'those' refer to 'small cars' or 'small cars that are more fuel-efficient'?

GMATGuruNY wrote: Incorrect: The manufacturer produced more cars this year than those last year.
Correct: The manufacturer produced more cars this year than last year.
The correct version implies the following comparison:
The manufacturer produced more cars this year than [it produced cars] last year.

In the following (OG2017 SC#758):
Prices at the producer level are only 1.3 percent higher now than a year ago and are going down, even though floods I the Midwest and drought in the south are hurting crops and therefore raised corn and soybean prices.

A: than a year ago and are going down, even though floods I the Midwest and drought in the south are hurting crops and therefore raised
B: than those of a year ago, and are going down, even though floods in the Midwest and drought in the south are hurting crops and therefore raising
C: than a year ago and are going down, despite floods in the Midwest and drought in the south, and are hurting crops and therefore raising
D: as those of a year ago and are going down, even though floods in the Midwest and drought in the south hurt crops and therefore raise
E: as they were a year ago and are going down, despite floods in the Midwest and drought in the south, and are hurting crops and therefore raising

Why A is wrong? In light of your examples about manufacture, we can omit the subject and verb and their presence could be implied as follows:

Prices at the producer level are only 1.3 percent higher now than [Prices at the producer level are] a year ago.


Where did I go wrong? I think it is like to your example:

'The manufacturer produced more cars this year than last year'

Thanks

Mo2men wrote:In the OA C, does 'those' refer to 'small cars' or 'small cars that are more fuel-efficient'?

Today's technology allows manufacturers to make small cars that are more fuel-efficient than those at any other time in production history.
Here, that serves to refer to small cars.
Thus, the portion in blue conveys the following:
Small cars [today] are more fuel-efficient than those at any other time in production history.
Here, those = small cars.
Implied comparison:
Small cars [today] are more fuel-efficient than small cars at any other time in production history.

In the following (OG2017 SC#758):

A: Prices at the producer level are only 1.3 percent higher now than a year ago and are going down, even though floods I the Midwest and drought in the south are hurting crops and therefore raised corn and soybean prices.

Why A is wrong?

Check my explanation here:
https://www.beatthegmat.com/og-2016-sc-90-t289707.html

GMATGuruNY wrote: Incorrect: The manufacturer produced more cars this year than those last year.
It seems to imply the following nonsensical comparison:
The manufacturer produced more cars this year than cars last year produced.

The implied meaning is incorrect because of the passive construction in the later part of the clause or because the phrase "cars last year produced" can refer to all cars, irrespective of the manufacturer, produced last year ?

gocoder wrote:

GMATGuruNY wrote: Incorrect: The manufacturer produced more cars this year than those last year.
It seems to imply the following nonsensical comparison:
The manufacturer produced more cars this year than cars last year produced.

The implied meaning is incorrect because of the passive construction in the later part of the clause or because the phrase "cars last year produced" can refer to all cars, irrespective of the manufacturer, produced last year ?

Incorrect: The manufacturer produced more cars cars this year than those last year.
Conveyed meaning:
The manufacturer produced more cars this year than those last year [produced cars].
Since those is standing in for cars, we get:
The manufacturer produced more cars this year than cars last year [produced cars].
The implied comparison is nonsensical.
This issue is that those last year seems to be serving as the SUBJECT of the second clause, implying-- nonsensically -- that cars produced cars.

Correct: The manufacturer produced more cars this year than last.
Conveyed meaning:
The manufacturer produced more cars this year than [the manufacturer produced cars] last [year].
This comparison is logical.