PrepTest 147

Incorrect. Even if there were some delays, the stimulus still establishes that delays were down, along with travel time and tailpipe pollution. Therefore, the presence of some delays would, at best, explain why pollution wasn't as low as it could be, not why it stayed about the same overall.

Correct. Argument or Facts:
Facts

Question Type:
Paradox

Stimulus Summary:
Electronic tolls decreased delays, decreased travel time per trip, and decreased pollution per trip, but overall pollution stayed the same.

Answer Anticipation:
The paradox here is that, while pollution per trip went down, overall pollution didn't. For there to be no reduction in overall pollution despite a per trip decrease, it must be the case that the total number of trips increased. Let's find an answer stating that!

Answer Explanation:
If more drivers are using the highway, then there are more cars on the road. While the per-trip pollution may go down, there are now more trips, and thus there could be more pollution overall.

Key Takeaway:
Whenever you see premises on the LSAT broken down in some way—per trip, per capita, per year—start to think about the total number of trips, capitas (yes, we know that's not a thing), or years. The net amount of something might be up or flat despite the per X amount being down.

Incorrect. Even if travel time for certain trips didn't decrease, it did for others, and so the paradox still stands—why didn't overall pollution go down?

Incorrect. Even if some people didn't make the switch, the stimulus notes that commute times and per-trip pollution went down, so the change had a measurable effect.