## What is this question assumption and how you guys solve this

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cathyhan

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Joined: Tue May 31, 2011 11:09 pm

### What is this question assumption and how you guys solve this

A large number of drivers routinely violate highway speed limit. Since driving at speeds that exceed posted limits is a significant factor in most accidents, installing devices in all cars that prevent those cars from traveling faster than the speed limit would prevent most accidents.
Which one of the following is an assumption on which the argument depends?
A. a person needs not be trained mechanic to install the device properly.
B. most accidents are caused by inexperienced drivers.
C. a driver seldom needs to exceed the speed limit to avoid an accident when none of the other drivers involved are violating the speed limit
D. most drivers who exceed the speed limit do so unintentionally.
E. even if the fines for speed-limit voilations were increased, the number of such violations would still not be reduced.

M.I.T. L. Rev.

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Joined: Tue Apr 19, 2011 11:17 am

### Re: What is this question assumption and how you guys solve this

C

Yeshia90

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Joined: Sun Apr 03, 2011 12:23 am

### Re: What is this question assumption and how you guys solve this

C, only because the other answers do nothing. Process of elimination.

crumpetsandtea

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### Re: What is this question assumption and how you guys solve this

Just FYI, you might want to list the PT/section/question number instead of the actual text, I don't think it's allowed on these forums to post LSAC copyrighted material in its exact form.

With that said, to help you out...the easiest way to get rid of answer choices in an assumption q is to negate the answer choice. If the stimulus DOES NOT make sense/follow logically once you negate the answer choice, then it is an assumption necessary for the argument to work.

A is not TCR because when you negate it, the stimulus still follows -- whether or not it can be installed by a non-mechanic has no bearing on accident prevention
B is is not TCR for a similar reason -- inexperienced drivers causing accidents has nothing to do with stim
C is TCR because when you negate it, the argument does not follow (if, even in cases where everyone is following the speed limit, drivers must still accelerate often to avoid accidents, the proposed solution does NOT prevent most accidents, since it keepsdrivers from avoiding accidents in which they must accelerate)
D is not TCR -- the stimulus still follows even if drivers exceed the speed limit intentionally
E is not TCR -- the stimulus says nothing about fines, so negating the answer choice has no effect on the logic in the stimulus.

bp shinners

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### Re: What is this question assumption and how you guys solve this

PSUdevon wrote:C, only because the other answers do nothing. Process of elimination.

The bolded is not right at all. C is right for the reasons that Crumpetsandtea stated. This is a necessary assumption question so you're looking for something without which the answer can't be valid (as opposed to a sufficient assumption question, where the answer choice fills the hole in logic to guarantee the validity). Negating the answer choices shows you why one is required by the argument (and is a fairly quick and sure way to check an answer you think is right).

Verity

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Joined: Sun Jan 30, 2011 11:26 pm

### Re: What is this question assumption and how you guys solve this

bp shinners wrote:
PSUdevon wrote:C, only because the other answers do nothing. Process of elimination.

The bolded is not right at all. C is right for the reasons that Crumpetsandtea stated. This is a necessary assumption question so you're looking for something without which the answer can't be valid (as opposed to a sufficient assumption question, where the answer choice fills the hole in logic to guarantee the validity). Negating the answer choices shows you why one is required by the argument (and is a fairly quick and sure way to check an answer you think is right).

+1. The other answers don't make sense, but that's not the only reason why C is right.

C, negated, would read: a driver seldom most of the time needs to exceed the speed limit to avoid an accident when none of the other drivers involved are violating the speed limit.

If this is true, then preventing a driver from accelerating would obviously prevent a driver's ability to avoid an accident most of the time.

So, if C is assumed, the argument follows.