Logical reasoning PrepTest 126 · Section 1 · Question 10

Incorrect. This answer is too broad. The stimulus provides one example of this, but it could be limited just to communication devices (or even just fax machines!).

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Must Be True

Stimulus Summary:
Fax machines rely on other fax machines to be useful, so incompatible formats between competitors hurt the fax industry. Manufacturers agreed to a common format that stopped this problem.

Answer Anticipation:
When a Must Be True question stem asks you to find a "proposition" supported by the stimulus, the correct answer is usually a generalization. Additionally, when the stimulus presents an unexpected outcome—much like it does in Paradox questions—that frequently plays into the correct answer.

Here, there is an unexpected outcome—a competitive industry was helped by the competitors cooperating with each other. That runs counter to the idea that competitors need to "beat" each other to make the most money, so it's likely going to factor into the correct answer.

Before forming a specific anticipation, one more consideration—the strength of the likely correct answer. The stimulus here provides only one example of this happening, so the generalization should be weak—it should speak to what is true "some" of the time, not most or all of the time. In fact, the stimulus specifically notes that the example it brings up is a bit of an outlier ("Unlike many machinesƒ"), so weaker is definitely in order.

With those two considerations explored, we can anticipate an answer similar to:
It's sometimes best for competitors to cooperate in some way.

Answer Explanation:
This answer is nice and weak, which is important because the stimulus provides only a single example that it doesn't note is representative of a general trend. And the example of the fax machine industry is one where cooperation helped the various competitors, so this is the correct answer.

Key Takeaway:
In a Must Be True question that presents generalizations as the answer, check to see how broad the stimulus is. Frequently, it'll bring up a single example, which means the correct answer will need to be weak since it's being backed up by such limited information. Also, don't look just at the language to determine the strength of the answer—see what that language is applying to. A perfect example of what we mean by this is answer choice (E)—focusing on the first word makes that answer appear weak and thus more likely to be correct, but it's actually quite broad/strong in applying to all industries. The weak language applies to the level of cooperation, not to the industries it applies to.

Incorrect. First, the stimulus discusses the incompatible formats of the fax machines, not the basic design. Second, it doesn't create a proportional relationship between the number of competitors and the amount of cooperation needed.

Incorrect. While this answer seems weak because of that opening "[s]ome," it actually applies to all industries (the weak modifier applies to the level of cooperation), so this answer is too broad to be inferred based on a single example.

Incorrect. The stimulus supports that cooperation can be beneficial in industries where products rely on other products of the same type, though it doesn't establish this is necessarily true of all such industries. And it definitely doesn't establish that this is true of only those industries.