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#8 - Eva: A "smart highway" system should be installed, one

ellenb
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Dear Powerscore,

I picked B for this question. I wonder why B is wrong and C is the right one?

Thanks

Ellen
Adam Tyson
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Hey there Ellen. Before we answer this question, have you tried the Assumption Negation Technique on these two contender answers? (I'm assuming that you have had the lesson on assumption questions - if not, my advice would be to not take any practice tests right now, but to focus your studies on your current lesson material and associated homework and supplemental material in the Online Student Center. There will be time for practice tests later, after you have a few more concepts and strategies in your toolkit.)

Give the Negation Technique a try here, and I think you will find that answer B, negated, really has no impact on the argument's conclusion, but answer C, negated, absolutely destroys it. That should be all you need to prove that C is the better answer of the two.
Adam M. Tyson
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ellenb
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So, for C if I negate it, I could say that "traffic flow in and around the cities is so congested that significant improvement is impossible" which if it is true than makes the conclusion invalid where Eva says will improve the traffic. (However, how can improve it, if it is impossible).

However, when I did it on B, "traffic lights, if coordinated by the system, would not assure a free flow of traffic" which I think in some way also affects the conclusion, because it is saying that the system will result in improved traffic flow. You mentioned that it does not have any impact, however, I think it does.

Thanks in advance

Ellen
Adam Tyson
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Good job on the negations - that's exactly the way I would have done them. Now it's just a matter of understanding the impact of those negations, and on that point I would have to disagree with you about the negation of answer choice B - I still say it has no impact.

Take a look at the author's evidence in support of her conclusion, which is that we should implement a smart highway system. Notice that traffic lights are not an element of her argument - she focuses instead on drivers having good, up to date information about alternate routes and where congestion is. Even if coordinated traffic lights would not assure free flow of traffic, her argument still sounds pretty good - informed drivers could make decisions that reduce congestion and thereby save money and improve productivity.

When we negate C, we find out that improvement is impossible. What does that do to the claim that we should implement the system? Completely destroys it - there's no point in implementing such a system if we cannot get any improvement as a result. The correct assumption answer, when negated, will typically obliterate the conclusion, either by directly contradicting it or by removing all of the supporting evidence for it. C fits that bill nicely, and so must be the correct answer.

There's one more way to look at this, and that's to remember the instructions for the LR section, which tell you to pick the BEST answer, not the "right" answer. Even if you read the negation of B as having some weakening effect on the argument, is it as strong an effect as that produced by the negation of C? Not even close. For that reason, C is the best answer (and that's how the authors of this test cover their backsides).
Adam M. Tyson
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PB410
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Hi,

I'm had trouble with this question's use of language. I originally chose C, but when I got further into the answer choice's language, I found the answer states "significant improvement" which still leaves room for improvement. The stimulus concludes that "Such a system, we can infer, would result in improved traffic." C when negate, "traffic flow in and around cities is NOW so congested that significant improvement is impossible." This still leaves room for some amount of improvement. It may not be significant, but it still can be an amount of improvement that matches the conclusion's "improved traffic."

Any thoughts?
Francis O'Rourke
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Hi Pb,

Eva states that a smart highway system would result in the following:

  1. improved traffic flow
  2. improvement in drivers' tempers
  3. a decrease in the considerable loss of money and productivity

I completely understand your point that the author only needs to assume the possibility of some amount of improvement in traffic flow. However, the author is assuming that whatever improvement in traffic would result in points #2 and #3 above.

If even a small improvement in traffic would result in these two things, then that traffic improvement is significant because of the other effects that it has.

Put more succinctly: even a small change would be significant.
gen2871
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Mr. Adam:

I really like how you said in the earlier reply, "The correct assumption answer, when negated, will typically obliterate the conclusion"

The textbook only says when negate the assumption answer choice, it should weaken the conclusion. But what you have just said makes perfect sense to me. Thank you!

So reiterate, the correct answer choices to Assumption questions is when you negate the answer choice, it will DESTROY the conclusion. correct?

Thank you!
Dave Killoran
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Hi Gen,

That's what you want it to do when negated, but depending on the centrality of the assumption, it may not completely destroy the argument, but only weaken it. This is why when I wrote the textbooks I only said it would weaken it; it will always weaken it, but it won't always destroy it :-D

Thanks!
Dave Killoran
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gen2871
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Ah. wow, thank you! I am extremely honored to get a response from the author of the book I have been reading and "sleeping" with. lol. Thank you!
Franny_i
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I am still learning the Assumption Negation technique and admittedly, I didn't use it for this question. That said, I picked A. I'm trying the technique in hindsight and yes, I do see that if C is negated, the argument pretty much falls apart. However, I'm also finding that negating A hurts the argument as well... Removing the "not," I got "on smart hwys, there would be the breakdowns of vehicles that currently cause traffic congestion." Doesn't this also weaken the conclusion or am I using the technique incorrectly? The same I feel could be said for B but I didn't pick that one since it soley specified traffic lights. I also see that A says "traffic congestion" instead of "traffic flow" and am wondering if this is where I dropped the ball?