Lobsters!!! Hard assumption

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Lobsters!!! Hard assumption

by henryhenry » Sun Feb 08, 2009 8:04 pm
Marine biology had hypothesized that lobsters kept together traps eat one another in response to hunger. Periodic checking of lobster traps,however,has revealed instances of lobsters sharing traps together for weeks. Eight lobsters even shared one trap together for two months without eating one another. The marine biologists' hypothesis,therefore, is clearly wrong.

The arguement against the marine biologists' hypothesis is based on which one of the following assumptions?

A) Lobsters not caught in lobster traps have been observed eating one another.

b) Two months is the longest known period during which eight or more lobsters have been trapped together.

c) It is unusual to find as many as eight lobsters caught together in one single trap.

d)Members of the other marine species sometimes eat their own kind when no other food source are available

e) Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger.

Please,give reason for your answer.
Thanks.
Source: — Critical Reasoning |

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by srn » Sun Feb 08, 2009 8:36 pm
IMO B.

This is how i came to the conclusion.

Marine biologists hypothesis is ' lobsters eat each other bcoz of hunger'.

The argument against the marine biologists is that ' lobsters donot eat each other if hungry'.

In the argument it is said that 'Eight lobsters even shared one trap together for two months without eating one another. Hence the hypothesis, is clearly wrong.'

The assumption therefore should be that 'Two months is the longest known period during which eight or more lobsters have been trapped together'.


Whats the OA answer.

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by Ian Stewart » Sun Feb 08, 2009 9:02 pm
srn wrote:IMO B.

This is how i came to the conclusion.

Marine biologists hypothesis is ' lobsters eat each other bcoz of hunger'.

The argument against the marine biologists is that ' lobsters donot eat each other if hungry'.

In the argument it is said that 'Eight lobsters even shared one trap together for two months without eating one another. Hence the hypothesis, is clearly wrong.'

The assumption therefore should be that 'Two months is the longest known period during which eight or more lobsters have been trapped together'.


Whats the OA answer.
I agree with your logic completely until the answer! :) As you say, 'The argument against the marine biologists is that ' lobsters donot eat each other if hungry'.' That is, the assumption is that the lobsters were hungry. E should therefore be the answer.
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Re: Lobsters!!! Hard assumption

by hypik21 » Sun Feb 08, 2009 9:45 pm
henryhenry wrote:Marine biology had hypothesized that lobsters kept together traps eat one another in response to hunger. Periodic checking of lobster traps,however,has revealed instances of lobsters sharing traps together for weeks. Eight lobsters even shared one trap together for two months without eating one another. The marine biologists' hypothesis,therefore, is clearly wrong.

The arguement against the marine biologists' hypothesis is based on which one of the following assumptions?

A) Lobsters not caught in lobster traps have been observed eating one another.

b) Two months is the longest known period during which eight or more lobsters have been trapped together.

c) It is unusual to find as many as eight lobsters caught together in one single trap.

d)Members of the other marine species sometimes eat their own kind when no other food source are available

e) Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger.

Please,give reason for your answer.
Thanks.
IMO E...lobsters eat each other if they are hungry...for the test to be valid, the lobsters should have been hungry in the experiment..

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by gmatmachoman » Sun Feb 08, 2009 11:02 pm
Really a tough one..

IMO (B)

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by srn » Mon Feb 09, 2009 12:01 am
Hi Stewart,

Please correct me if I am wrong.

The assumption should bridge the gap between the premise and the conclusion.

Premises - Eight lobsters even shared one trap together for two months without eating one another.

Conclusion - lobsters kept together do not eat one another.

Thus the assumption should be that 'Two months is the longest known period during which eight or more lobsters have been trapped together.'
If this was not so we could not have concluded that 'lobsters kept together do not eat one another'
as the only info given in the argument is the 'eightl obsters even shared the trap together for 2 months'.

If I am wrong plz let me know where I made the mistake.
I do not agree with E because though it leads to the conclusion, it doesn't bridge the gap between the premise and the conclusion.

Also Henry, whats the OA answer?

Thanks.

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by Ian Stewart » Mon Feb 09, 2009 1:45 am
srn wrote:Hi Stewart,

Please correct me if I am wrong.

The assumption should bridge the gap between the premise and the conclusion.

Premises - Eight lobsters even shared one trap together for two months without eating one another.

Conclusion - lobsters kept together do not eat one another.

Thus the assumption should be that 'Two months is the longest known period during which eight or more lobsters have been trapped together.'
If this was not so we could not have concluded that 'lobsters kept together do not eat one another'
as the only info given in the argument is the 'eightl obsters even shared the trap together for 2 months'.

If I am wrong plz let me know where I made the mistake.
I do not agree with E because though it leads to the conclusion, it doesn't bridge the gap between the premise and the conclusion.

Also Henry, whats the OA answer?

Thanks.
Perhaps it would be unusual to say that "eight lobsters even shared one trap together for two months without eating one another" if you knew about an example of, say, ten lobsters sharing a trap for ten months. Still, whether the person knew about a case where ten lobsters shared a trap for three months or not, it would not affect the argument; we don't need to assume that two months is the longest time eight lobsters have shared a trap for the argument to make sense. That is, it's not an underlying assumption.

As you correctly noted above, there is a key phrase in the original argument: "Marine biology had hypothesized that lobsters kept together traps eat one another in response to hunger." The counterargument concludes by saying that marine biologists are wrong. That assumes that the lobsters were indeed hungry; if the eight lobsters who were confined together for two months never acted 'in response to hunger' because they weren't hungry, then they have nothing at all to do with the argument made by the marine biologists.
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by Shivani Varma » Mon Feb 09, 2009 2:27 am
Argument against the Marine biologists Hypothesis is based on which of the following?

Contrary to what the biologists believe the lobsters have not eaten each other.That they have been observed not eating each other for 8 days.
the fact that they mention even eight Lobsters shared a trap they are probably assuming that there might have been times when they were hungry as more food would obviously be required to keep them satisfied.

Anaysis of the option

a-A) Lobsters not caught in lobster traps have been observed eating one another. ---- No information so out of scope

b) Two months is the longest known period during which eight or more lobsters have been trapped together. NO information given about that either .. We should not introduce new information into the problem. the GMAT doed not require u to have any addtional information about the subject that is being spoken about.

c) It is unusual to find as many as eight lobsters caught together in one single trap.
Again does not make sense

d)Members of the other marine species sometimes eat their own kind when no other food source are available

OUT OF scopre, introducing new information irrelevant

e) Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger... ASsuming that they were hungry but still did not eat each other is sufficient to prove the hypothesis of the BIOlogists wrong!!!

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by henryhenry » Mon Feb 09, 2009 8:13 pm
OA is E. This is a standard LSAT question. I have been doing tons of these questions but i found a few of them extremely hard.

Thanks everyone.

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by graem83d » Sun May 15, 2016 2:47 am
I will Go with option B in this case