Logical Reasoning

PT7 · S4 · Q1 In 1974 the speed limit on highway

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In 1974 the speed limit on highways in the United States was reduced to 55 miles per hour in order to save fuel.

Conclusion (it follows that)

The 1974 reduction in the speed limit saved many lives.

Evidence

In 1974, the speed limit on highways in the United States was reduced to 55 miles per hour 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.

Evaluate

This argument presents a correlation between the reduction of the speed limit and a decrease in highway fatalities and concludes a causal relationship from it, meaning this is an Explain Curious Fact pattern.

Curious Fact: What caused the sharp decline in highway fatalities?

Author's Explanation: The reduction in the speed limit to 55 miles per hour led to many lives being saved.

To strengthen the argument, we can provide more evidence that supports this explanation or rule out other factors that could have explained the decrease in fatalities.

Goal

Let's find an answer that increases the plausibility of the author's explanation for the decline in highway fatalities or rules out other significant contributing factors.

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

The 1974 fuel shortage cut
Opposite Impact
This weakens by providing an alternate explanation for the decrease in fatalities. If there was way less driving for more than a year, that itself could cause a decrease in fatalities.
4% picked this
There was no decline in
No Impact
The information about the twelfth year post-reduction doesn't impact the argument about the effects of the initial reduction. It deals with a time outside the critical periods presented in the evidence (the first year and the subsequent 10 years). Whether the speed limit change did or didn't make a difference, it would be likely for that difference to level off by twelve years later, once it's become the status quo.
2% picked this
Since 1974 automobile manufacturers have
Opposite Impact
This introduces another potential factor for reducing fatalities, so it suggests an alternative explanation for the decline, which would weaken the argument rather than strengthen it.
4% picked this
Correct
The fatality rate in highway
Why this is right
This answer strengthens the argument because it directly supports the causal link between reducing the speed limit and saving lives by showing that accidents at higher speeds result in higher fatalities. Thus, the lower speed limit plausibly contributed to life savings by reducing the incidence of high-speed accidents.
Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.
80% picked this
Motorists are more likely to
Opposite (if anything)
This suggests that accident avoidance depends more on matching speed than on the speed limit itself, which could undermine the argument that the reduction to 55 mph, specifically, was the key factor in reducing fatalities.
10% picked this

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