SC Comparison Question

Question

Hi,

I'm looking for help understanding the rules behind comparisons. Are these the right rules? (Nouns being compared are bolded below)

Descriptor is in between --> we need to compare nouns
* the  white cedar  used has four times the tensile strength  steel has  - INCORRECT
* the  white cedar  used has four times the tensile strength of  steel  - CORRECT

Descriptor is possessed --> we need to compare possessives
* because the  white cedar's tensile strength  is four times as strong as  steel  - INCORRECT
* because the  white cedar's tensile strength  is four times as strong as  steel's  - CORRECT

Descriptor is before --> we need to compare descriptors
* because the  tensile strength of white cedar  is four times as strong as  steel  - INCORRECT
* because the  tensile strength of white cedar  is four times as strong as  that of steel  - CORRECT

I think these would apply to other comparisons that people could be confused with like "does", "that", etc. Can someone check if these are the right rules? Am I missing any to know? Thanks.

gentvenus · Answer

All the correct statements look fine to me!

Rogermoris · Answer

All the comparisons are right in my opinion.

abhishekdadarwal2009 · Answer

1 Tensile strengths are compared-correct
2 Tensile strengths are compared-correct
3 Tensile strengths are compared-wordy but correct

EducationAisle · Answer

Hi  chenkc805 , this doesn't look incorrect to me.

chenkc805 · Answer

I thought so too but this OG question proves me wrong: (GMAT link, sorry I can't post links yet because I'm too new of a member): chinese-public-buildings-erected-under-a-construction-code-of-the-sung-305962

EducationAisle · Answer

Hi  chenkc805 , not really.

In this OG question, with option C, the sentence is:

Chinese public buildings erected under a construction code of the Sung dynasty have withstood earthquakes well because the white cedar that was used in them has four times the tensile strength steel has, and the timber frame, incorporating many joints and few nails, is flexible.

Official explanation of why C is wrong:

The comma after has breaks up the sentence in such a way that only the great tensile strength of white cedar is offered as an explanation of the buildings' ability to withstand earthquakes, rather than both white cedar's tensile strength and the timber frame's flexibility. The statement regarding the timber frame's flexibility is mentioned simply as a separate fact not falling under the scope of because.

Notice that OG does  not  point to any errors in the comparison construct of this option. So, C is correct from a comparison perspective.

chenkc805 · Answer

What about option B? I don't see how Option B is technically wrong. Is it because "used in them" is ambiguous, since "them" could refer to Chinese public buildings or earthquakes?

For reference:
Option B: (B) used in them has four times the tensile strength of steel has and the timber frame, incorporating
Option B in the sentence: Chinese public buildings erected under a construction code of the Sung dynasty have withstood earthquakes well because the white cedar  used in them has four times the tensile strength of steel has and the timber frame, incorporating  many joints and few nails, is flexible.

EducationAisle · Answer

Hi  chenkc805 , B is basically stating:

the white cedar has four times the tensile strength of steel  has

has  is a big  red  flag here. Generally speaking, after a  preposition  ( of  in this case), one would only expect a  noun  (e.g.  steel ) and not a  verb  ( has ).

chenkc805 · Answer

Would changing "of" to "that" make the use of "has" correct? See below:
 the white cedar has four times the tensile strength  that  steel  has

Would the following also be correct, changing "of" to "as"? I ask because whenever there's multiplication involved in a comparison, "as" is often used.
* the white cedar used has four times the tensile strength as steel

Apologies if these questions are a bit tedious. Comparisons are not my strength

EducationAisle · Answer

Yes, this is almost a restatement of option C (in terms of comparison).  that  (a relative pronoun) is correctly modifying  tensile strength .

From a multiplication perspective, following would be a better construct:

The white cedar is four times as strong as steel.

* Couldn't really fit-in  tensile  appropriately, in the above sentence:).

SC Comparison Question

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