PrepTest 103

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Strengthen

Stimulus Summary:
CAR System - Warns pilots where other planes are and tells them to take evasive action
Conclusion - Passengers are safer on planes with than without a CAR System
Wrinkle - CAR Systems frequently give false positives (a warning when there's no plane nearby)

Answer Anticipation:
Let's talk about this stimulus first. It starts with a description of a system, which will almost always be background. From there, it hops right into a premise that's going to support a conclusion in the same sentence—we know that since it starts with "Because." That conclusion is comparative, discussing the relative safety of passengers on planes with and without a specific system. And then it introduces a wrinkle—the system sometimes gives a false alarm.

With the argument outlined, we can hop into the flaw here. We know that the system warns pilots of nearby planes, allowing them to take evasive action and avoid collisions. That seems to support the conclusion that it makes passengers safer!

However, there's no indication that it doesn't have any other impact on the ability of the pilot to work. Maybe the alarm startles pilots and causes them to crash. Maybe evasive action causes more danger than being warned by air control to shift. There's even a note that the system "frequently" has false positives—maybe that itself creates danger.

Since the argument is assuming that any danger of having the system—and dealing with the false positives—is outweighed by the warnings provided by the system, we should look for answers that address alternative dangers, and establish they're less of a big deal than the possibility of collision (which, to be fair, sounds pretty bad).

(And yes, this is the exact same Anticipation as the last question. The Anticipation step for Strengthen with Necessary Premise questions and Strengthen questions is essentially the same!)

Answer Explanation:
The argument was about relative safety, and this answer is about safety, so we should dig in to see if it strengthens the argument. The stimulus noted that passengers are safer on planes that give warnings of collisions, leading to evasive actions, as compared to planes that don't have such warnings. If the evasive actions that are taken in response to these warnings pose no risk to passengers, then that increases the safety of this system, strengthening the argument. This answer is therefore correct.

Key Takeaway:
Strengthen with Necessary Premise questions and Strengthen questions have a lot of overlap, especially in the Anticipation step. You should be identifying the assumption of the argument and anticipating answers that support that assumption.

The difference between the two is mainly in the answer choices. While all Strengthen with Necessary Premise answers will strengthen the argument, not all answers that Strengthen an argument will serve as necessary premises. For instance, (A) here isn't necessary for the argument to work, since there could be some risk to the evasive actions taken as long as those risks are much lower than the risks of a collision.

Incorrect. This answer is out of scope in talking about what happens when planes are on the ground, thus making the collision system useless.

Incorrect. Even if collisions are rare, they still exist. And as such, a plane less likely to end up in one is safer than a plane more likely to do so.

Incorrect. If anything, a majority of warnings being false positives would argue against the effectiveness of the system. That said, it doesn't actually weaken the argument, as we have no way of knowing if the 37% of warnings that were valid didn't increase safety enough to overcome any decrease in safety due to the 63% false warnings.

Incorrect. How the system works—without any connection to safety—is out of scope of the argument.