GMATPREP Comparison SC_ NOTES.

[gmat_perfect]

Hi Guys,

I have collected some comparison sc's from GMATPREP. I am posting those in different posts so that every single question can have more attention.

Please participate on the discussion.

Thanks.

[GMATMadeEasy]

They are from GMAT Prep or PowerPrep ?

Just want to confirm .

[gmat_perfect]

They are from GMAT Prep or PowerPrep ?

Just want to confirm .

From GMATPREP.

I have collected about 70 questions on comparison from GMATPREP. I think that after discussing those, we will have a solid idea about the comparison sc.

Thanks.

[GMATMadeEasy]

Thanks to Ron for his great explanations on this topic. Almost all notes are based on his explanations .

Note 1: () Please pay attention to each and every word
When you state comparisons, make sure of these three things:
1. Meaning must be absolutely clear.
2. The entities being compared must be grammatically and logically parallel. (Beware there might be ellipsis in such construction)
3. Helping verb does not have to be repeated if both verbs are supposed to be in same tense and meaning is clear.

[GMATMadeEasy]

Note 2 :

Two important notes for comparison of two items: (Manhattan SC)
1. To compare two items, prefer the form "er", if it exists otherwise "more X" form.
2. Adverb that ends in "ly", do not change this to "er" form to compare rather use "more ly" form.

He runs quickly. He runs quicker than me. (Incorrect) - Quicker does not exist.
He runs quickly. He runs more quickly than me. (Correct)

[GMATMadeEasy]

Note 3 : (partially from other sources as well and my work)

"Twice":
"Twice" CANNOT function as an object of the preposition such as "by".
"... increased by more than twice .." -- WRONG!

"Twice" is an adverb.
"twice Y" / "X times Y" can definitely be used as an appositive.
If you say "twice as many", then this construction should be paired with a countable noun.
e.g., twice as many dogs --> "dogs" is a countable noun.
If you said "twice as much", then this construction should be paired with an uncountable noun.
e.g., twice as much water --> "water" is an uncountable noun

If the noun in question is already an explicitly numerical quantity, then you should use neither "much" nor "many". Instead, you should just use "twice" or "double" by itself.
e.g., twice the increase --> "increase" is an explicitly numerical quantity.
twice as much as the increase... --> incorrect; Redundant

The GMAT would almost certainly prefer 'twice' to 'two times', because 'twice' is nice - it's more concise.

On a similar note, "DOUBLE" is an adjective/veb and can not modify verb, but since "Twice" is an adverb it can modify Verb.
Example: -
The same amount of acreage produces double the apple. -- WRONG
The same amount of acreage produces twice as many apples. -CORRECT

[GMATMadeEasy]

Note 4 :
"twice as many as":
"..., twice as many as ..." is an APPOSITIVE modifier. Appositives must modify some noun that comes immediately before the comma.
Example: The number of people flying first class on domestic flights rose sharply in 1990, doubling the increase of the previous year.
"... rose sharply in 1990, twice as many as ... " -- WRONG!!
"... rose sharply in 1990, doubling the increase of the previous year." -- RIGHT!!

COMMA + -ING is ALWAYS an adverbial modifier, and ALWAYS modifies the entirety of the preceding clause (whether you want it to or not!)
In this case, that's precisely what we want to do, so this is the winner.

NOTE:
If you have an appositive modifier as an ABSTRACT NOUN - such as "strategy", "figure", "statistic", "findings", "situation", "change", "difference" etc. - then such an appositive may be allowed to describe the entire situation described in the preceding clause.

[GMATMadeEasy]

Note 5 : (From OG 12)
Limitations is a countable quantity. So it must be modified by "FEWER" and NOT by "less".
"Equal" is generally used for UNCOUNTABLE quantities such as "equal justice" and NOT COUNTABLE quantities such as "people".
"People" is countable. "People" is the plural of "person". We can count people.

[GMATMadeEasy]

Note 6 (Very important)

VERB TENSE SHIFT
if there is a change in verb tense between the two halves of the comparison, then you MUST include the verb in both halves. (if the verb is omitted in the second part of the comparison, then the implication is that the tense is the same in both halves.)
so: Heating-oil prices are expected to be higher this year than they were last year --> correct
BUT if you wrote
Heating-oil prices are expected to be higher this year than last year
then this would be incorrect, since there must be a tense shift between what is happening this year and what happened last year.

[GMATMadeEasy]

Note 7 : (For rather than and Instead of , it is incomplete in my opinion)

"Rather than" Vs "Instead of": (Educated guess: generally rather than is correct in answer choices)
"Rather than" is preferable to use for VERBS. (Particularly infinitives)
"Instead of" is preferable to use for NOUNS.

"Contrast": Correct idioms for contrasts:
* In contrast to X, Y
* In contrast with X, Y
* Unlike X, Y
*Just as X, so Y
Incorrect Idiom:
* As contrasted with X, Y
Just as X, so Y" is the CORRECT construction where X and Y must be grammatically PARALLEL elements. (Some official questions are there based on this)

[gmat_perfect]

@ GMATMadeEasy,

Thanks for your effort. I am seeing your posts. Those are very interesting. Would you please collect all the explanations of the comparison sentence?

Thanks.

[GMATMadeEasy]

Note 8 : (Need an expert to review this and summarise an brain-digestable format )
"Greater than" Vs "More than": (Source Kaplan 800)
"Greater than" --> When describing numbers alone (greater than one hundred)
"More than" --> When describing the numbers of objects OR When making comparisons. (more than one hundred fish)
Greater than 10, more than 10 percent
WRONG: The rare Monkey species is not extinct; its NUMBERS are now suspected to be much MORE than before.
RIGHT: The rare Monkey species is not extinct; its NUMBERS are now suspected to be much GREATER than before.

Source Manhattan 4th Edition
Higher ...over (Incorrect): I will have HIGHER bill OVER last year. WRONG
Higher .. than (Correct): I will have HIGHER bill THAN last year. RIGHT
Source : Ron's explanation on Manhattan site
In formal written english, if you are talking about an increase in a single statistic, you use GREATER. If you are counting things, and NOT referring to 'the number' or 'the population' or any other single statistic, you use MORE - always as an adjective or adverb.
The population of Filipinos is greater than it was 10 years ago.
There are more Filipinos than there were 10 years ago.
Need more clarification and examples on this .
Can be apply /extraplate the above logic to following as well.
Greater - > Lower
More - > Less

[GMATMadeEasy]

Note 9 : (Special thanks to Ron ) ;
A side note by me: A SC given by GMAT should make complete sense without any assumption.
Compared to/with for STATISTICS: (very Important)
If you say "compared with/to" for statistics, you should cite BOTH statistics in the comparison.
The expression "compared to/with" does NOT imply any sort of direction to the comparison; i.e., it gives no hint as to greater/less/like/unlike. Therefore, you need to give both of the relevant statistics, or else the statement won't make any sense.

Examples:
"The unemployment rate in Esteria last month was 5.3%, compared to the rate in Burdistan." -- INCORRECT! This makes no sense. We have absolutely no idea what is going on with the rate in Burdistan.
"The unemployment rate in Esteria last month was 5.3%, compared to a rate of 7% in Burdistan." -- CORRECT!
Both statistics are cited.
"In contrast to":
If you say "in contrast to", then you don't HAVE to mention both statistics. Although you still can mention.
Examples:
"In contrast to the corresponding rate in Esteria, the unemployment rate in Burdistan fell last month." -- CORRECT!
In this case, the "in contrast to" construction implies that the Esterian rate went up. We don't actually have to say this explicitly.
But, if you want, you can mention both statistics:
"In contrast to the corresponding rate in Esteria, which rose by 0.5%, the unemployment rate in Burdistan fell by 0.3% last month." -- ALSO CORRECT

[GMATMadeEasy]

Round 1 of posts is over. Let's get them analysed and supported with some examples by all users .

Will move to advance concepts late evening or tomorrow morning . (Comparison + ellipsis + subject+ along with parallelism) .

We should PM also some gurus to review the above posts to ensure that I have not introduced any error during "my own" interpretation of the solutions.

[mundasingh123]

Hi Guys,

I have collected some comparison sc's from GMATPREP. I am posting those in different posts so that every single question can have more attention.

Please participate on the discussion.

Thanks.

i remember you not answering my quest when i asked u abt the source.
i believe you posted the questions before bringout this thread.You could have posted this in the subject line of each comparison quest so that ppl who havnt taken the gmat prep tests could avoid it because this could inflate their scores.You havnt even posted the OA .
It will not be possible for People who would attempt 20 quests today without knowing whether their answers are right or not , to check out the answers when they log on the next day ,when the forum will be cluttered with new posts the next day.
This is a public forum and i feel there should be a format.