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A. Heating-oil prices are expected to be higher this year than last because refiners are paying about $5 a barrel more for crude oil than they were B. Heating-oil prices are expected to rice higher this year over last because refiners pay about$5 a barrel for crude oil than they did

C. Expectations are for heating-oil prices to be higher this year than last year's because refiners are paying about $5 a barrel fr crude oil more than they did D. It is the expectation that heating-oil prices will be higher for this year over last because refiners are pauing about$5 a barrel more for crude oil now than what they were

E. It is expected that heating-oil prices will rise higher this year than last year's because refiners pay about $5 a barrel for crude oil more than they did Source: OG-13 OA: A My doubt: From what I understand is that we are comparing "Heating-oil prices this year" with "heating-oil prices last year". Choice A is comparing "Heating-oil prices this year" with "last year". How is this the valid comparison? Shouldn't the comparison be "than last year's" or "than those of last year" to make it a parallel comparison? Need free GMAT or MBA advice from an expert? Register for Beat The GMAT now and post your question in these forums! ### GMAT/MBA Expert Kasia@EconomistGMAT GMAT Instructor Joined 21 May 2012 Posted: 646 messages Followed by: 142 members Thanked: 322 times Wed Mar 13, 2013 7:02 am Answer A makes a comparison between the price that refiners are paying now with the price that they were paying last year. The sentence uses ellipsis. A part of the verb "were paying" was elided for the sentence to become more concise. Compare: Heating-oil prices are expected to be higher this year than last because refiners are paying about$5 a barrel more for crude oil than REFINERS were PAYING last year.

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rjain84 Senior | Next Rank: 100 Posts
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Wed Mar 13, 2013 7:09 am
Kasia@EconomistGMAT wrote:
Answer A makes a comparison between the price that refiners are paying now with the price that they were paying last year. The sentence uses ellipsis. A part of the verb "were paying" was elided for the sentence to become more concise.
Compare:
Heating-oil prices are expected to be higher this year than last because refiners are paying about \$5 a barrel more for crude oil than REFINERS were PAYING last year.
Hey Kasia, Thanks for explaining but I got the comparison in the second half of the sentence. What I didn't understand was the comparison in the first half - "Heating-oil prices are expected to be higher this year than last". How are they parallel? The sentence is comparing "Heating-oil prices this year" with "last year". IMO, that's illogical.

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Wed Mar 13, 2013 7:46 am
rjain84 wrote:
My doubt:

From what I understand is that we are comparing "Heating-oil prices this year" with "heating-oil prices last year".

Choice A is comparing "Heating-oil prices this year" with "last year". How is this the valid comparison? Shouldn't the comparison be "than last year's" or "than those of last year" to make it a parallel comparison?
ELLIPSIS is the omission of words whose presence is understood.
Answer choice A:
HEATING-OIL PRICES are expected to be higher this year than [HEATING-OIL PRICES were] last [year].
Here, the bracketed words are omitted, but their presence is understood.
The omission is warranted because the SAME PRICES are being compared from one year to the next.
CITY A'S PRICE is expected to be higher this year than CITY A'S PRICE was last year.
CITY B'S PRICE is expected to be higher this year than CITY B'S PRICE was last year.
CITY C'S PRICE is expected to be higher this year than CITY C'S PRICE was last year.

All together:
HEATING-OIL PRICES are expected to be higher this year than HEATING-OIL PRICES were last year.
Since each clause refers to the SAME PRICES, the comparison is made more concise by omitting the subject from the second clause:
Heating-oil prices are expected to be higher this year than last.

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rjain84 Senior | Next Rank: 100 Posts
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Wed Mar 13, 2013 7:59 am
GMATGuruNY wrote:
rjain84 wrote:
My doubt:

From what I understand is that we are comparing "Heating-oil prices this year" with "heating-oil prices last year".

Choice A is comparing "Heating-oil prices this year" with "last year". How is this the valid comparison? Shouldn't the comparison be "than last year's" or "than those of last year" to make it a parallel comparison?
ELLIPSIS is the omission of words whose presence is understood.
Answer choice A:
HEATING-OIL PRICES are expected to be higher this year than [HEATING-OIL PRICES were] last [year].
Here, the bracketed words are omitted, but their presence is understood.
The omission is warranted because the SAME PRICES are being compared from one year to the next.
CITY A'S PRICE is expected to be higher this year than CITY A'S PRICE was last year.
CITY B'S PRICE is expected to be higher this year than CITY B'S PRICE was last year.
CITY C'S PRICE is expected to be higher this year than CITY C'S PRICE was last year.

All together:
HEATING-OIL PRICES are expected to be higher this year than HEATING-OIL PRICES were last year.
Since each clause refers to the SAME PRICES, the comparison is made more concise by omitting the subject from the second clause:
Heating-oil prices are expected to be higher this year than last.
That's a wonderful explanation. Thanks Mitch! But I still have my doubts. How can we be 100% sure if the presence of omitted words is understood? In this sentence, for example, the comparison is creating ambiguity. There are 2 possibilities -

1. Heating-oil prices this year are higher than the heating-oil prices of last year.
or, more subtle
2) Heating-oil prices this year are higher than last year. (Here, we are comparing two things this year - "heating-oil prices" and "last year". It's weird and can't be possible in the real world but its ambiguous at the same time).

neha24 Senior | Next Rank: 100 Posts
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Wed Mar 13, 2013 8:47 am
Quote:
2) Heating-oil prices this year are higher than last year. (Here, we are comparing two things this year - "heating-oil prices" and "last year". It's weird and can't be possible in the real world but its ambiguous at the same time).
i guess u r taking ambiguity in a wrong sense .things are ambiguous when 2 or more sensible meaning can be arrived ."heating oil prices" can nowhere be compared to "last year" ."price of one year" can be compared to "price of another year"

though i have some question to Mitch and Kasia abt ellipses : when u making a tense shift as we doing in this sentence (we are comparing prices that are going to be in future to prices that were in the past) aren't we suppose to make that tense visible in the sentence and not just put it elided as we have done here

rjain84 Senior | Next Rank: 100 Posts
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Wed Mar 13, 2013 9:38 am
neha24 wrote:
Quote:
2) Heating-oil prices this year are higher than last year. (Here, we are comparing two things this year - "heating-oil prices" and "last year". It's weird and can't be possible in the real world but its ambiguous at the same time).
i guess u r taking ambiguity in a wrong sense .things are ambiguous when 2 or more sensible meaning can be arrived ."heating oil prices" can nowhere be compared to "last year" ."price of one year" can be compared to "price of another year"
If we go by your logic then this sentence should also be correct -

Amy chances of success are higher than Betty.

Since comparing "Amy chances of success" with "Betty" is nonsensical, there is only one possibility left. It can only compare Amy chances of success with Betty chances of success and therefore there is no ambiguity in the sentence.

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Wed Mar 13, 2013 9:54 am
rjain84 wrote:
GMATGuruNY wrote:
rjain84 wrote:
My doubt:

From what I understand is that we are comparing "Heating-oil prices this year" with "heating-oil prices last year".

Choice A is comparing "Heating-oil prices this year" with "last year". How is this the valid comparison? Shouldn't the comparison be "than last year's" or "than those of last year" to make it a parallel comparison?
ELLIPSIS is the omission of words whose presence is understood.
Answer choice A:
HEATING-OIL PRICES are expected to be higher this year than [HEATING-OIL PRICES were] last [year].
Here, the bracketed words are omitted, but their presence is understood.
The omission is warranted because the SAME PRICES are being compared from one year to the next.
CITY A'S PRICE is expected to be higher this year than CITY A'S PRICE was last year.
CITY B'S PRICE is expected to be higher this year than CITY B'S PRICE was last year.
CITY C'S PRICE is expected to be higher this year than CITY C'S PRICE was last year.

All together:
HEATING-OIL PRICES are expected to be higher this year than HEATING-OIL PRICES were last year.
Since each clause refers to the SAME PRICES, the comparison is made more concise by omitting the subject from the second clause:
Heating-oil prices are expected to be higher this year than last.
That's a wonderful explanation. Thanks Mitch! But I still have my doubts. How can we be 100% sure if the presence of omitted words is understood? In this sentence, for example, the comparison is creating ambiguity. There are 2 possibilities -

1. Heating-oil prices this year are higher than the heating-oil prices of last year.
or, more subtle
2) Heating-oil prices this year are higher than last year. (Here, we are comparing two things this year - "heating-oil prices" and "last year". It's weird and can't be possible in the real world but its ambiguous at the same time).
When one clause is compared to another, the two clauses generally will be PARALLEL in form.
Since this year serves as a MODIFIER in the first clause, the default interpretation is that its COUNTERPART in the second clause -- last year -- also serves as a modifier.
Thus, there is no ambiguity: we know that PRICES this year are being compared to PRICES last year.

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rjain84 Senior | Next Rank: 100 Posts
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Wed Mar 13, 2013 10:11 am
GMATGuruNY wrote:
rjain84 wrote:
GMATGuruNY wrote:
rjain84 wrote:
My doubt:

From what I understand is that we are comparing "Heating-oil prices this year" with "heating-oil prices last year".

Choice A is comparing "Heating-oil prices this year" with "last year". How is this the valid comparison? Shouldn't the comparison be "than last year's" or "than those of last year" to make it a parallel comparison?
ELLIPSIS is the omission of words whose presence is understood.
Answer choice A:
HEATING-OIL PRICES are expected to be higher this year than [HEATING-OIL PRICES were] last [year].
Here, the bracketed words are omitted, but their presence is understood.
The omission is warranted because the SAME PRICES are being compared from one year to the next.
CITY A'S PRICE is expected to be higher this year than CITY A'S PRICE was last year.
CITY B'S PRICE is expected to be higher this year than CITY B'S PRICE was last year.
CITY C'S PRICE is expected to be higher this year than CITY C'S PRICE was last year.

All together:
HEATING-OIL PRICES are expected to be higher this year than HEATING-OIL PRICES were last year.
Since each clause refers to the SAME PRICES, the comparison is made more concise by omitting the subject from the second clause:
Heating-oil prices are expected to be higher this year than last.
That's a wonderful explanation. Thanks Mitch! But I still have my doubts. How can we be 100% sure if the presence of omitted words is understood? In this sentence, for example, the comparison is creating ambiguity. There are 2 possibilities -

1. Heating-oil prices this year are higher than the heating-oil prices of last year.
or, more subtle
2) Heating-oil prices this year are higher than last year. (Here, we are comparing two things this year - "heating-oil prices" and "last year". It's weird and can't be possible in the real world but its ambiguous at the same time).
When one clause is compared to another, the two clauses generally will be PARALLEL in form.
Since this year serves as a MODIFIER in the first clause, the default interpretation is that its COUNTERPART in the second clause -- last year -- also serves as a modifier.
Thus, there is no ambiguity: we know that PRICES this year are being compared to PRICES last year.
Makes sense to me now. Thank you very much Mitch for clarifying this! Would really appreciate if you could give some examples of sentences that compare clauses and use ellipsis for the comparison.

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Wed Mar 13, 2013 7:33 pm
Quote:
rjain84 wrote :If we go by your logic then this sentence should also be correct -

Amy chances of success are higher than Betty.

Since comparing "Amy chances of success" with "Betty" is nonsensical, there is only one possibility left. It can only compare Amy chances of success with Betty chances of success and therefore there is no ambiguity in the sentence.
the ambiguity i was talking of i will illustrate with an example :
a leopard cannot catch a wild beast as fast as cheetah

now this sentence is ambiguous because in this we can get 2 sensible and compatible meaning

a leopard cannot catch a wild beast as fast as cheetah can

or

a leopard cannot catch a wild beast as fast as it can a cheetah

the sentence that u were talking of oil prices isn't ambiguous coz the other meaning that u derived was nonsensical

now for ur this sentence :Amy chances of success are higher than Betty.

this sentence is wrong not ambiguous because the comparison is wrong at the first place also amy's chances sud have been used (i feel that u forgot amy's)

u need it this way :Amy's chances of success are higher than Betty's

tanviet Legendary Member
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Fri Apr 05, 2013 8:57 am
when dose the elipsis is considered not ambiguous?

if we do ellipsis, we may create the ambiguity.

thank you experts for taking part in this questions.

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