The average individual’s cost of going into space is estimated at a

Question

The average individual’s cost of going into space is estimated at a fraction of the price per economy ticket of transatlantic airplane travel by the end of the 21st century.

(A) The average individual’s cost of going into space is estimated at a fraction of the price per economy ticket of transatlantic airplane travel by the end of the 21st century.

(B) The average individual’s cost by the end of the 21st century of going into space is estimated at a fraction of the price per economy ticket of transatlantic airplane travel.

(C) By the end of the 21st century, the average individual’s cost of going into space is estimated at a fraction of the price per economy ticket of transatlantic airplane travel.

(D) To go into space, the cost to the average individual is estimated at a fraction of the price per economy ticket of transatlantic airplane travel by the end of the 21st century.

(E) It is estimated that by the end of the 21st century the cost to the average individual of going into space will be a fraction of the current price per economy ticket of transatlantic airplane travel.

What is wrong with option 'C'.

daagh · Accepted Answer

If you look at this from the idiom angle, well perhaps A through D are instant outcasts, for it is never possible to estimate something at some precise thing There is always an element of prediction, speculation, guesstimation, or approximation involved in estimation. 
Therefore, 'estimate to be' 'estimate that' are better than 'estimate at'. Estimated at is more in tandem with locations and not with numbers at least.

E then is the sole survivor. But one can rest assured such an open and shut question is not going to appear in the reality of GMAT. 
The essence of the argument is that if one or two choices had the idiom 'estimated to be' rather than 'estimated at', what would be the correct answer? I give below an edited version in line with the above thought.(I hope MGMAT will have no objection for this practice session. )

The average individual’s cost of going into space is estimated at a fraction of the
price per economy ticket of transatlantic airplane travel by the end of the 21st
century.

(A) The average individual’s cost of going into space is estimated at a fraction
of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.

(B) The average individual’s cost by the end of the 21st century of going into
space is estimated at a fraction of the price per economy ticket of transatlantic
airplane travel.

(C) By the end of the 21st century, the average individual’s cost of going into
space is estimated to be a fraction of the price per economy ticket of transatlantic
airplane travel.

(D) To go into space, the cost to the average individual is estimated to be a fraction
of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.

(E) It is estimated that by the end of the 21st century the cost to the average
individual of going into space will be a fraction of the current price per economy
ticket of transatlantic airplane travel.

We now have a 2 estimated at +2 estimated to be +1 estimated that. The question is wide open now to munch.

abhimahna · Answer

The average individual’s cost of going into space is estimated at a fraction of the
price per economy ticket of transatlantic airplane travel  by the end of the 21st
century.   Dangling modifier.

(A) The average individual’s cost of going into space is estimated at a fraction
of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.  INCORRECT, for the reason mentioned above.

(B) The average individual’s cost by the end of the 21st century of going into
space is  estimated at a  fraction of the price per economy ticket of transatlantic
airplane travel.  INCORRECT IDIOM USAGE

(C) By the end of the 21st century, the average individual’s cost of going into
space is  estimated at  a fraction of the price per economy ticket of transatlantic
airplane travel.  INCORRECT IDIOM USAGE

(D) To go into space, the cost to the average individual is  estimated at a f raction
of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.  INCORRECT IDIOM USAGE

(E) It is estimated that by the end of the 21st century the cost to the average
individual of going into space will be a fraction of the current price per economy
ticket of transatlantic airplane travel.  CORRECT And CLEAR

TheRzS · Answer

Hi Daagh According to MGMAT guys "estimated at" is not a correct idiom, although there are some doubts on that. Please see the link below https://www.manhattanprep.com/gmat/foru ... t7889.html That leaves us with C, D and E. C has "the average individual’s cost" . The use of possessive is problematic. D has "To go into space, the cost to the average individual" , which, I think, violates infinitive of purpose. So E still is the correct answer, IMO. Please let me know the correct answer and your expert advise. Best RzS

daagh · Answer

RzS

My edited version:  The average individual’s cost of going into space is estimated at a fraction of the price per economy ticket of transatlantic airplane travel by the end of the 21st century.

(A) The average individual’s cost of going into space is estim
ated at a fraction of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.

(B) The average individual’s cost by the end of the 21st century of going into
space is estimated at a fraction of the price per economy ticket of transatlantic
airplane travel.

(C) By the end of the 21st century, the average individual’s cost of going into
space is estimated to be a fraction of the price per economy ticket of transatlantic
airplane travel.

(D) To go into space, the cost to the average individual is estimated to be a fraction
of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.

(E) It is estimated that by the end of the 21st century the cost to the average
individual of going into space will be a fraction of the current price per economy
ticket of transatlantic airplane travel.

If E is the answer for the original topic under issue, then it should be the correct answer for the altered example too, since there is no difference between them. Therefore, you are on the dot.

However, in the other two choices, namely C and D, my point was to highlight the problem in meaning. Please note that the intent of the passage is to compare the anticipated future cost of space travel to the current price of the transatlantic travel. It is not a comparison between the cost of the both the two listed travels in the future time namely by the end of 21st century. The transatlantic cost is of today and that is why E is correct. That is the crux.

(C) By the end of the 21st century, the average individual’s cost of going into space is estimated to be a fraction of the price per economy ticket of transatlantic airplane travel.

Your reason: C has "the average individual’s cost". The use of possessive is problematic. - Of course, you mean the cost of the individual going into space' is perhaps better. 
 
My reason: You see, the introductory modifier "By the end of the 21st century" stands for both the travel costs at the end of 21st century. The function of an introductory modifier is to modify the entire events that follow. That is substantively different from the original intent. That is why this wrong logically.

(D) To go into space, the cost to the average individual is estimated to be a fraction of the price per economy ticket of transatlantic airplane travel by the end of the 21st century.

Your reason for D: has "To go into space, the cost to the average individual", which, I think, violates infinitive of purpose. 
My reason: 1. in this choice, the future cost trans - Atlantic travel that is by the end of the 21st century is wrongfully compared with the probable future cost of the space trip. Why is this wrong? Because you cannot compare between an unknown space cost with a yet another unknown cost. 
2. Dictionally, the average cost of travel is substantively different from the cost to the average individual. This is also a change in meaning.

Am I right?

shekyonline · Answer

The average individual’s cost of going into space is estimated at a fraction of the
price per economy ticket of transatlantic airplane travel by the end of the 21st
century.

(A) The average  individual’s cost  of going into space is  estimated at  a fraction
of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.

(B) The average  individual’s cost  by the end of the 21st century of going into
space is  estimated at  a fraction of the price per economy ticket of transatlantic
airplane travel.

(C) By the end of the 21st century, the average  individual’s cost  of going into
space is  estimated at  a fraction of the price per economy ticket of transatlantic
airplane travel.

(D) To go into space, the cost to the average individual is  estimated at  a fraction
of the price per economy ticket of transatlantic airplane travel by the end of
the 21st century.

(E) It is estimated that by the end of the 21st century the cost to the average
individual of going into space will be a fraction of the current price per economy
ticket of transatlantic airplane travel.

Correct

TaN1213 · Answer

Absolutely brilliant explanation for addressing the change of meaning in C. Nicely done modifications to the options too! Thanks for the edited version  daagh .

Bunuel · Answer

MANHATTAN REVIEW OFFICIAL EXPLANATION:

The first thing you have to do is figure out what the basic structure of this sentence is. X is Y. Something is estimated. That is critical verb in this sentence. Therefore, you need to find an answer choice that has a matching order of words. Despite the fact that it appears to be fairly complex, there is only one answer that even comes close to that core structure. Choice E is the correct answer. Once you realize what the core is, eliminating the rest of the choices should be fairly simple.

PanigaleV4 · Answer

Nicooo13 · Answer

Some people mentioned that "estimated at" was not a correct idiom. I am not native but I see nowhere on Internet that this idiom is not correct. Can someone kindly confirm?

Gaurav2896 · Answer

Hi  DmitryFarber   VeritasKarishma  can you please help me one doubt in option E , i rejected it because -> It is estimated that by the end of the 21st century  the cost to the average individual  of going into space will be a fraction of the current price per economy ticket of transatlantic airplane travel. This cost to average individual strike me , (what is average individual , shouldn't it be average cost to individual. ) so I chose C.Is this "average individual" correct here?

FOr those who saying estimated at is incorrect , below is GmatPrep question  With surface temperatures estimated at  minus 230 degrees Farenheit, Jupiter's moon Europa has long been considered far too cold to support life, and with 60 square miles of water though to be frozen from top to bottom.

KarishmaB · Answer

All 5 sentences are talking about an average individual. Whether you write "average individual's cost" or "cost to the average individual", what is being averaged is the individual, not the cost. 
"average individual" just means "common man" here. 
I do understand that "average cost" to an individual makes more sense but the sentence here wants to say "cost to common man"

Also, "estimated to be" is better than "estimated at" even if the non underlined part of a GMAT Prep question does use it.

But more importantly, option (E) made far more sense to me than did the other options.

What is estimated? that by the end of the 21st century the cost to the average individual of going into space will be a fraction of the current price of airplane travel.
This is the estimate. That this cost will be a fraction of that current cost. Makes sense.

When you estimate a figure, you would say "estimated to be 5 million dollars". When you say "estimated to be a fraction of that current price", does it make a lot of sense? The estimate is that it will be a fraction of that cost. "A fraction" itself shows a very vague quantity. Then my estimate isn't yielding much value. I can estimate something to be half of or quarter of something else. But can I estimate something to be a fraction of something else? Both show approximation.

Hence option (E) is the best.

Palpable · Answer

Agree with the reasoning here. I eliminated E because it misses a comma after ' by the end of 21st century, the cost'.

I picked option B because the 21st century modifier is only used for the cost of space travel, whereas the transatlantic flight cost is kept without any such modifier and I inferred that it's the present cost.

Where did my thinking go wrong?

Posted from my mobile device

The average individual’s cost of going into space is estimated at a

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Sentence Correction (SC - EA only) Questions

The average individual’s cost of going into space is estimated at a

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards