In 1974 the speed limit on highways in the United States was reduced

I choose D

(A) The 1974 fuel shortage cut driving sharply for more than a year. - out of scope

(B) There was no decline in the rate of highway fatalities during the twelfth year following the reduction in the speed limit.
- weakens the argument

(C) Since 1974 automobile manufacturers have been required by law to install lifesaving equipment, such as seat belts, in all new cars. - weakens

(D) The fatality rate in highway accidents involving motorists driving faster than 55 miles per hour is much higher than in
highway accidents that do not involve motorists driving at such speeds. - my choice

(E) Motorists are more likely to avoid accidents by matching their speed to that of the surrounding highway traffic than by driving at faster or slower speeds. - weakens the argument. The flow can move at a speed higher or lower than the allowed, and the probability of an accident depences on the driving style

It was between D and E finally chose D.

Between D and E.. Only D talks about fatality rate.. So D wins clearly

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there is a little confusion here
D has at least 2 pattern. The first is to compare one to each other group. The second is it is the only option that has direct link with the matter in the argument.

Conclusion: the drop in the speed limit saved many lives


WHY: the speed limit was reduced to 55, and after one year the rate of highway fatalities dropped by 15 %, and over the next ten years it dropped another 25 percent.

Looking at this core, I noticed two problems:

1. the author seems to be playing with percentages. Just because the percentages went down, it doesn't mean more lives were saved. It could be that the drop in the speed limit led to many more people driving, so even though we had a drop in the rate of fatalities, more people were dying each year.

2. Author mistakes correlation for causation.

Just because the drop in speed limit coincided with the drop in the rate of fatalities, it doesn't mean the two are related. It could be that something else, such as a national campaign to promote better driving, was the cause.

To strengthen the first issue, we have to show that the number of people driving did not increase to such an extent whereby we could not conclude that many lives were saved.

To strengthen the second issue, we have to rule out the possibility that some other factor caused the drop. It's important to note that when we are given correlation/causation flaws on Strengthen and Weaken questions, the answer choice usually tests our understanding of this. So it is likely that we will be tested on the second issue.

A. this was very tempting for me at first because it seems to get at our first issue. That there was no increase in driving. However, if that's that case, it would provide an alternative cause for the drop in fatalities, so it can't be correct.

B. is irrelevant because we don't know anything about the 12th year. Maybe the speed limit was increased again.

C. gives us an alternative cause, which means it would weaken the argument.

D. gives us a classic way to strengthen a correlation flaw on the LSAT - by showing that when you don't have the cause, you won't get the effect.

55mph --> lower rate

D: don't have 55mph --> rate is not as high

This strengthens our correlation and is the correct answer.

E. not impact on argument.

Cause and Effect passage, my favorite!

Lowering speed limit (CAUSE) means saving many lives (EFFECT)

(A) The 1974 fuel shortage cut driving sharply for more than a year. ???

(B) There was no decline in the rate of highway fatalities during the twelfth year following the reduction in the speed limit. Why this option contradicts the premise?

(C) Since 1974 automobile manufacturers have been required by law to install lifesaving equipment, such as seat belts, in all new cars. WEAKEN by providing alternate cause. Eliminate on a solid ground.

(D) The fatality rate in highway accidents involving motorists driving faster than 55 miles per hour is much higher than in
highway accidents that do not involve motorists driving at such speeds. BINGO! strengthen the premise or CAUSE that states that >55 means more fatal accidents.

(E) Motorists are more likely to avoid accidents by matching their speed to that of the surrounding highway traffic than by driving at faster or slower speeds. Doesn't talk about fatality.

Skywalker18
Hello!
I just want to say this: the detail with which you provide explanations across the forum is just extraordinary. Be it CR,RC or SC. Way too good.

Thank you!

In 1974 the speed limit on highways in the United States was reduced to 55 miles per hour in order to save fuel. In the first 12 months after the change, the rate of highway fatalities dropped 15 percent, the sharpest one-year drop in history. Over the next 10 years, the fatality rate declined by another 25 percent. It follows that the 1974 reduction in the speed limit saved many lives.

Which one of the following, if true, most strengthens the argument?

(A) The 1974 fuel shortage cut driving sharply for more than a year. - WRONG. Weakener. Alternative reason behind such a drop.

(B) There was no decline in the rate of highway fatalities during the twelfth year following the reduction in the speed limit. - WRONG. Irrelevant.

(C) Since 1974 automobile manufacturers have been required by law to install lifesaving equipment, such as seat belts, in all new cars. - Weakener. Alternative reason behind such a drop.

(D) The fatality rate in highway accidents involving motorists driving faster than 55 miles per hour is much higher than in highway accidents that do not involve motorists driving at such speeds. - CORRECT. As easy as it can get.

(E) Motorists are more likely to avoid accidents by matching their speed to that of the surrounding highway traffic than by driving at faster or slower speeds. - WRONG. Weakener. Alternative reason behind such a drop.

Answer D.

E is trap answer....
I believe understanding the trap answers are equally important

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