The comparison in the context is between a total that is 469, 000 for both X and Y in 1914 and a number that is 2x469000 for x alone in 1929. The intention of the comparison is to establish that the truck production alone exploded enormously between the two time references. The mission is amply achieved in B, when we refer to 469,000 of 1914 as that number that had doubled to 938000 in 1929 for truck production alone.
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I think twice is not underlined.



B.

1. trucks "by themselves" came off - Seems like the trucks started moving by themselves, like in the horror movies. C and E are out. I think the same can be said about D too.
2. I choose B.
In A, "twice the number of trucks" means the 1929 truck count. Twice the number of trucks in 1929, cannot come out in 1929 itself.
By bringing "that", the number referred is 469,000 - 1914 total count.

The sentence is not making any good sense at all. What is the source of this question? Or is there any typo. 'themselves' or 'alone' sounds terrible.

Anyways, only B is best among the worst.

'that' refers to the preivous number of 469k rightly. Without the relative pronoun 'that' the sentence lack the element of 'to what extent or to what degree'.

To add to this...with A) twice the number could refer to 'twice 1929'

I chose B because I felt the need for 'that'.

So, if I had to calculate the question mathematically, I would calculate the number of trucks in 1929 as (2 * X) and 'that' in B helps me tells what the number X is i.e 429 K.

I agree with venksune , B is the best of worst .
I am sure this is not a GMAT question not even close .

In 1914 a total of 469,000 cars and trucks were produced in the United States, but in 1929 almost twice the numbers of trucks alone came off the assembly lines.

A. the numbers of trucks alone - 'numbers of' is always wrong
B. that number of trucks alone - CORRECT
C. the number of trucks by themselves
D. as many trucks themselves - 'as many as' is the correct idiom.
E. as many trucks by themselves - same as D.

Between A and B the difference is subject-verb agreement in the non-underlined portion?

hi
the numberS of.....is always incorrect for GMAT..
always use the number of....and this is always singular
a number of .....is always plural

hope it helps
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I think it helps to first figure out what the sentence is really trying to convey...

The sentence tells us that In 1914 a total of 469,000 cars and trucks were produced in the United States,
but in 1929 almost twice that number of trucks alone came off the assembly lines.

I think we need a relative pronoun to refer to the number in 1949.
Answer choices :
A. the numbers of tucks alone : 'twice the numbers of' is incorrect.
B. that number of trucks alone : Correct
C. the number of trucks by themselves : the trucks themselves did not come out of the assembly line.
D. as many trucks themselves :the trucks themselves did not come out of the assembly line
E. as many trucks by themselves :the trucks themselves did not come out of the assembly line

Cheers

In 1914 a total of 469,000 cars and trucks were produced in the United States, but in 1929 almost twice the numbers of tucks alone came off the assembly lines.

The correct idiom is "as many as"
D and E out

A) the numbers of trucks alone
WRONG :- twice of what number ?? we need a digit or a reference to a digit.

B) that number of trucks alone
CORRECT:- twice that number of truck alone ; twice of 4696000.

C) the number of trucks by themselves
WRONG:- "alone" , "by themselves" is redundant. Both means the same thing.

D) as many trucks themselves
WRONG IDIOM

E) as many trucks by themselves
WRONG IDIOM


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in 1914 -- 469,000 cars plus trucks
in 1929 -- twice of 469,000 trucks alone

A. the numbers of tucks alone
twice the numbers --- which numbers?? we don't know.

B. that number of trucks alone
twice that number -- here that number refers to 469,000

C. the number of trucks by themselves
twice the number -- which number?
what themselves is used here for? we don't know.

D. as many trucks themselves
as many as sets the comparison. only one "as" is used. another "as" is missing.

E. as many trucks by themselves
same as D.
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In 1914 a total of 469,000 cars and trucks were produced in the United States, but in 1929 almost twice the numbers of tucks alone came off the assembly lines.

A. the numbers of trucks alone
B. that number of trucks alone

Between the numbers of trucks and the number of trucks:

You have some x number in 1914, and the then you have twice that number in 1929. The 1929 number has to be a definite and particular number. If we call it numbers, then we are implying that the number, in fact, could be many numbers such x, y, or z and so on. This is absurd. After all twice x is also one number as one can see.

That is the reason that A is out.
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In 1914 a total of 469,000 cars and trucks were produced in the United States, but in 1929 almost twice the numbers of tucks alone came off the assembly lines.

A. the numbers of tucks alone - twice the number is unclear
B. that number of trucks alone - Correct
C. the number of trucks by themselves - twice the number is unclear
D. as many trucks themselves - Idiom As x as
E. as many trucks by themselves - Idiom As x as

Answer B
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Imo B
This is a comparison question .
So we have to set up proper comparison between elements.
The original sentence talks about the number of 469000 Cars and trucks .
So we have to compare the that number .The number of trucks increased twice of 469000


Sent from my ONE E1003 using GMAT Club Forum mobile app

C is eliminated straight forward because of the use of THEMSELVES
Trucks by THEMSELVES came off.....

If we don't use THAT, the sentence would be
TWICE the NUMBER of trucks alone came off - from this sentence, it is not clear which number are we referring to. In order to refer to number 469,000, we need to use THAT.

It is the question from one of the GMAT PREP MOCK

The Number of is the right word not the numbers of ; By Themselves illogical meaning ; As many As is the correct diction .

The Number of is singular
Gmat Loves That

B is the only option .
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