Increasing the speed limit to 65 miles per hour or more on highways is

Question

Competition Mode Question

Increasing the speed limit to 65 miles per hour or more on highways is dangerous and only leads to more accidents. Whenever the highway speed has been increased, accident rates have increased in that state. Maine raised its turnpike speed to 65 mph in November, and more fatal accidents occurred in December than any other month in the year. Highway fatalities in December and January combined were up 18% from November.

All of the following are valid criticisms of this argument EXCEPT

A. it does not explain why the speed limit was originally set at 55 mph.
B. it does not specify whether the accident rate increase was in accidents only on the highways where the speed limit was increased or on all highways.
C. it does not consider other possible causes for increases in accidents, such as winter weather driving conditions in Maine.
D. it only cites statistics for one state.
E. it does not acknowledge that speed is not the only cause of accidents.

eakabuah · Answer

Conclusion: setting the speed limit at 65mph or greater is dangerous and only results in more accidents.
Premise 1: Increased highway speed leads to increased accident rates in a state.
Premise 2: Maine raised its turnpike speed to 65mph in November, more accidents occurred in December than any other month.
Premise 3: Highway fatalities went up by 18% in December and January with respect to November.

The right answer in my view has to be A. 
The reason why the speed limit was raised from 55mph to 65mph on Maine's turnpike does not criticize the argument in any way. The reason can be as flimsy as it can be, citing it does not provide any form of criticism to the argument made by the author.

All the other choices, however, provide valid criticisms to the argument.
Option B: The argument does not specify where the specific highways on which the accidents occurred. It might be that most of the accidents did not occur on the turnpike highways where the speed limits were raised to 65mph, so this a valid criticism of the argument.

Option C: If there are other possible causes of accidents such as winder weather driving conditions within the period in which the data has been provided, then, failure to include such considerations in the argument is a valid criticism for the argument.

Option D: For a general conclusion to be drawn on an issue of such nature, it will be prudent that more than one state is considered. Else the conclusion should be based solely on Maine state. Hence failure to include other states is a valid criticism.

Option E: There could be other causes of accidents apart from speed. How about the nature of the road? Do the accidents occur during nighttime when visibility is poor? Do the highways have adequate street lighting on the highways to improve visibility on the road? Are the roads foggy during the time the accidents occur? These are valid criticisms.

unraveled · Answer

Increasing the speed limit to 65 miles per hour or more on highways is dangerous and only leads to more accidents. Whenever the highway speed has been increased, accident rates have increased in that state. Maine raised its turnpike speed to 65 mph in November, and more fatal accidents occurred in December than any other month in the year. Highway fatalities in December and January combined were up 18% from November.
All of the following are valid criticisms of this argument EXCEPT

Argument says that increase in accidents is caused by increase in highway speed limit. Giving the example of Maine argument elaborates its claim.

A. it does not explain why the speed limit was originally set at 55 mph. - CORRECT. It does not either criticize or strengthens the argument since reason to find why speed limit was mph earlier is irrelevant in the context of the argument.
B. it does not specify whether the accident rate increase was in accidents only on the highways where the speed limit was increased or on all highways. - WRONG. Answer to the option helps explain the gap between accidents data of highway with increased limit and highways without increased limit.
C. it does not consider other possible causes for increases in accidents, such as winter weather driving conditions in Maine. - WRONG. Other causes if explained would weaken the argument as presented.
D. it only cites statistics for one state. - WRONG. This points a flaw in the argument for its biased claim.
E. it does not acknowledge that speed is not the only cause of accidents. - WRONG. If cause of accidents is other than speed then argument is weakened to make such a claim.

IMO Answer A.

daagh · Answer

Ans must be D as the sample size of statistics of just one state{ Maine is a stat I suppose) seems to be too small for a wholesome national statement. This is just my instinct.

madgmat2019 · Answer

A. it does not explain why the speed limit was originally set at 55 mph.....invalid
B. it does not specify whether the accident rate increase was in accidents only on the highways where the speed limit was increased or on all highways......valid
C. it does not consider other possible causes for increases in accidents, such as winter weather driving conditions in Maine.
D. it only cites statistics for one state.......valid
E. it does not acknowledge that speed is not the only cause of accidents......valid

OA: A

ParamjitDasGMAT · Answer

A is the best answer. First, let us rephrase the question as a standard strengthen/weaken/assumption etc. question type. Essentially, this is an "EXCEPT" question, which could be re-framed as "All of the following WEAKEN the argument EXCEPT". With this in mind, let us approach the argument:

Here, the argument states that raising the highway speed limit to 65 mph or more is dangerous and leads to more accidents. It further goes on to cite accident-based statistics related to Maine, which support the idea that the speed limit should not be increased in Maine. The data confirm that whenever the speed limits have increased, so have the accident rates. The figures also show that increased accident rates (up by 18%) since when Maine raised its turnpike speed in November.

Now, let us think of the possible ways to weaken the argument. One fundamental assumption made by the author is that correlation = a causal connection. This absolutely does not have the case. For example, there could be other (unrelated to speed) causes for the increased accident rates, and the connection between increasing the highway speed limit and greater accident rate could be purely coincidental (and not necessarily a cause-effect relationship). Therefore, any option(s) which state something along this line of reasoning would weaken the argument. Since this is a "WEAKEN Except" question, we want to  eliminate  the options that weaken the argument. This eliminates C and E.

Furthermore, another way to weaken the argument would be to question the data provided. The author is drawing an overly broad, generalized conclusion based on "increasing the speed limit on highways", whereas the statistics he provides are only for Maine. Clearly, based on statistics for just country/state/town, we cannot draw a generalization. In other words, we cannot go from the premise of "Apples are red" to the conclusion "Fruits are red"  . This eliminates D.

Lastly, the accident data show that there was an overall 18% combined increase in the highway fatalities in the months of December and January in Maine. However, this does not differentiate between highways where the speed limit was increased vs those where it remained the same. It could be the case that most of the increase in the overall accident rate was occurring on highways where the speed limit remained the same, and was due to a reason entirely unrelated to speed (for example, wild animals jumping in front of cars, a gang of robbers being active in the area, etc.]. Once again, the author fails to distinguish between correlation and causality, and this line of reasoning could weaken the argument. This eliminates B.

Option A is the correct answer. Option A actually acts as a strengthener, because if increasing the speed limit to 65mph increased the accident rates, then the argument would serve as a perfectly adequate explanation of why the original speed limit was on the lower side of 55 mph. Since Option A strengthens the argument, this must be the correct answer to our "WEAKEN Except" question.

exc4libur · Answer

ARGUMENT
  increasing limit on h-ways is dangerous and leads to more accidents; 
  whenever limit is increased, accidents increase; 
  ie. Maine increased in Nov and more fatal accidents occurred in Dec than any month year.

FIND WEAKEN
B. if accidents were on all h-ways, it might have been something else, besides limit increase, this weakens;
C. if accidents in Maine were caused by weather, or other factors, then this attacks the premise, this weakens;
D. if all other states that increased limit, didn't show an increase in accidents, then Maine is an exception, this weakens;
E. if the accidents were caused by something else, this weakens;

Answer (A): knowing y the limit was 55 doesn't attack the premise or weaken the argument.

effatara · Answer

Obviously (A). The statement attempts to establish that higher speeds cause more road accidents and, to support this argument, it cites certain statistics showing an increase in accidents in Maine after the speed limit there was raised. The reasons why the speed limit in Maine was originally set at 55 mph are irrelevant here.

(B) Valid. The Maine turnpike is in fact a stretch of highway that passes through only 4 out of the 16 counties of Maine. It appears from the statement that the speed limit was not increased in the other highways. If there was a spike on the other highways as well despite the fact that the speed limit was not increased in those then this statement stands thoroughly debunked.

(C) Valid. Wet icy conditions, poor visibility due to snow and sleet and and slippery roads could very well be major contributing factors.

(D) Valid. The second sentence of the statement asserts that "wherever the speed limit on highways has been increased accidents have increased in that state" but statistics for other states have not been cited in support of this contention. Statistics have been cited only for Maine and that too only for the turnpike which constitutes a small fraction of the total road network in that state.

(E) Valid. That it does not and even if it did it would have to show that there was no change in the other contributing factors in order to be conclusive.

2794Aditya · Answer

Option A: 
Nowhere in the argument was it mentioned that the earlier speed was  55mph , making this a wrong assumption. It is irrelevant why the speeds are low, because increase in speeds beyond 65mph are anyhow leading to accidents. Therefore, this js not a valid criticism on the argument. We can keep this option, though a wrong assumption and wait for a better choice.

Option B:
Clearly, the argument states that increase in  highway  speed limits have increased the accident rates in the  state  ( which includes the internal roads in a district, city or a village ). No increase specifically on the highways was stated in the argument. A valid criticism. WRONG ANSWER CHOICE

Option C:
The argument doesn't consider other factors contributing to the increase in the rate of accidents. The increase in the accidents maybe due to unforeseen harsh weather conditions. A valid criticism. WRONG ANSWER CHOICE.

Option D:
True, the argument talks only about one state. The reason behind the increase in accident rates in Maine maybe due to other reasons (for eg: low maintenance in the previous months). In some other adjacent state, the increase might have lead to decrease in the accidents. A valid criticism. WRONG ANSWER CHOICE.

Option E:
It does  not  acknowledge that speed is  not  the only cause of accidents. Double negation. Precisely, it states that speed is the  only cause  of accidents.  But what speeds ?  As per the argument, increase in speeds to more than 65mph leads to more accidents. Increase in speeds  caused more accidents. If at all, speeds more than 65mph lead to greater number of accidents, but accidents have occured prior to increase in speeds. Hence, this is not a valid criticism.

Out of A and E, A is irrelevant and a wrong assumption that speed were 55mph. Hence, option E is the right choice.

Posted from my mobile device

Bunuel · Answer

Official Explanation

Correct Answer: A

The issue in the argument is whether increased speed limits are dangerous, so the argument should focus on proving that this is the case. The fact that the argument does not discuss why the speed limit was originally set at 55 mph is essentially irrelevant, so it is not a valid criticism of the argument. All of the other options, however, express valid criticisms and point out significant flaws in the reasoning.

VerbalBot · Answer

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Increasing the speed limit to 65 miles per hour or more on highways is

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Increasing the speed limit to 65 miles per hour or more on highways is

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