sentence correction problem

Question

hey guys was wondering if anyone could explain this one:

Rock samples taken from the remains of an asteroid about twice the size of the 6-mile-wide asteroid that eradicated the dinosaurs  has been dated to be 3.47 billion years old and thus is  evidence of the earliest known asteroid impact on earth.

A. has been dated to be 3.47 billion years old and thus is
B. has been dated at 3.47 billion years old and thus
C. have been dated to be 3.47 billion years old and thus are
D. have been dated as being 3.47 years old and thus
E. have been dated at 3.47 billion years old and thus are

arvs212 · Answer

E. have been dated at 3.47 billion years old and thus are

>>though i was a bit confused with the use of 'at' in option E and 'to be ' in option C.

would like some pointers.

nookway · Answer

The correct answer is E

Rock samples taken from the remains of an asteroid about twice the size of the 6-mile-wide asteroid that eradicated the dinosaurs  has been dated to be 3.47 billion years old and thus is  evidence of the earliest known asteroid impact on earth.

A. has been dated to be 3.47 billion years old and thus is  Incorrect Subject-Verb agreement Subject (Rock Samples) is plural but the verbs 'has' and 'is' are singular. Also incorrect Idiom dated to be. 
B. has been dated at 3.47 billion years old and thus  Incorrect Subject-Verb agreement Subject (Rock Samples) is plural but the verbs 'has' is singular. 
C. have been dated to be 3.47 billion years old and thus are  Correct Subject-Verb agreement but incorrect Idiom dated to be. 
D. have been dated as being 3.47 years old and thus  Incorrect Idiom dated as 
E. have been dated at 3.47 billion years old and thus are  Correct Subject-Verb agreement Also correct Idiom 'dated at'.

goldeneagle94 · Answer

I thought it is C.

I learned something new - idiom "dated at".

Thanks !!

pm4553 · Answer

Ditto. I went with C too. Didn't know about the idiom.

sudeep · Answer

dated at, new addition to the list of idioms

rs2010 · Answer

dated to be means it is still tentative while dated at shows the certainty.

Here sentence demands certainty therefore, E is correct.

sudeep · Answer

So does that means both idioms are correct but differs in context of certainty?

bigoyal · Answer

sc-rock-samples-15613.html

bigoyal · Answer

Just found the below link, while searching on google:
https://www.manhattangmat.com/og12-sentence-corr.cfm

which explains:
Dated must go with "at", not "to be", when you express an age: This fossil has been dated AT 10,000 years old, not TO BE 10,000 years old. In contrast, a seemingly similar word, estimated, must be used in precisely the opposite way with ages (This fossil has been estimated TO BE 10,000 years old, not AT 10,000 years old).

aknine · Answer

Great, thanks everyone, even I did not know that 'dated at' was an idiom. 
I also thought it would be C.

smashingpumpkins · Answer

Thank you very much..I thought it was (C). Got to add a new idiom to my master list

sudeep · Answer

So can someone conclude for this:

are both the idioms, dated to be and dated at, correct?
If yes, what do they imply - the certainity or the way it is mentioned in sc-rock-samples-15613.html#p98593

Wats the OA?
the link sent by bigoyal suggest OA to be C

bigoyal · Answer

Actually E should be the correct answer.
Correct idiom use is - "dated at X years old" or "estimated to be X years old"

scorpio7 - please let us know the OA ?

rs2010 · Answer

OA is E. I got this question in Prep 2 exam.

Natia · Answer

good question, didn't know the idiom "date at", thanks

Prometoh · Answer

First split : have is better

Second split : date at is a correct idiom

Thus, E wins

miweekend · Answer

Opps..I think this is really a dangerous question, I picked E becuase dinosaurs -- Plural!!!!! i do not understand how could the "have been" is pointing to ROCK SAMPLE???

can anyone pls explain...thanks

VerbalBot · Answer

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sentence correction problem

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