QUESTION TEXT: Reducing speed limits neither saves lives nor…
QUESTION TYPE: Flawed Reasoning
CONCLUSION: Reducing speed limits doesn’t save lives or help the environment.
REASONING: Cars will spend more time on the road, where they can pollute and could get into an accident.
ANALYSIS: According to this argument, we’d all be safest if we drove at 150 mph, and got to our destinations really, really fast. See the flaw?
Cars aren’t as dangerous if they’re going slowly. And cars may pollute more at high speeds even if they are the road for less time.
___________
- If motorists ignore speed limits then the argument is stronger. Speed limits certainly won’t make a difference if they are ignored.
- The conclusion was only about pollution and safety.
- This fact would strengthen the argument. The argument claims more cars are dangerous.
- CORRECT. Emissions might increase quite a bit with speed. Time is not the only factor.
- The argument doesn’t assume that road time is the only factor. The author of the argument might agree that drunk driving increases the risk of accidents, for example.

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Jeez, I just have a really hard time understanding why D is right– how is saying that “reduced speed limits don’t protect the environment” because “cars spend more time on the road” the same thing as assuming total emission being primarily determined by time? I feel like that is quite a logical leap
It follows directly from what the author said. If emissions weren’t directly affected by time, then the author couldn’t conclude that more time on the road is worse than less, even if vehicles were slower.
Put it another way: suppose someone said “It is better for this car to be on the road for 90 minutes in certain circumstances than on the road for 60 minutes in other circumstances”. This is the opposite of the author’s argument. What does this person need to assume? They have to assume that some factor other than time is important, because looking at time alone the first situation seems much worse.
would you categorize the flaw in this argument one of causation or?
I would categorize this as “ignores obvious factor” or a common sense error. Most people know that higher speeds are dangerous, but the author ignores this obvious issue.
On the emissions issue, the flaw is the same: the author ignores the obvious possibility that emissions change in intensity based on speed.
I think this is a “tricky” question since the LSAT assumes you will hone in on the flaw related to driving speed and accidents, which seems to be a more obvious flaw than that related to pollution..I almost selected E for that reason but realized this flaw was not present.
I agree with what you said about the trickiness of this question, but you said “I realized this flaw was not present” (as it relates to the safety/accident premise) But it was, wasn’t it? The author does not “justify” why “spewing exhaust into the air” increases the risk of collisions. .. ?
The author does not make the claim that spewing exhaust into the air increases the collisions. Instead, they make the claim that the more time the car spends on the road, the greater the risk of colliding with other vehicles. Saul said that the author does not make the flaw in (E), which is true. (E) says that the argument presumes that cars run a significant risk of collisions only if they spend a lot of time on the road. The stimulus does not go so far as to say this is the only contributing factor to collisions.
Thanks. I realize I read the sentence wrong—I thought he author was saying as a result of the spewed exhaust, there is a greater risk of more collisions. But the sentence was saying, more time on the road=1) more exhaust & 2) more collisions, separately. thanks for the clarification!