Logical reasoning PrepTest 142 · Section 4 · Question 25

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Flawed Parallel Reasoning

Stimulus Summary:
Most disapprove of the PM because she supports an increase to the income tax.Theresa supports an increase to the income tax, so she probably approves of the PM.

Answer Anticipation:
This argument starts by establishing a trait that's true of most members of a group—most in the group who disapprove of the PM do so because they disagree with her stance on increasing the income tax. It then establishes that a specific person—Theresa—doesn't share that trait, she's probably not a member of the group.

Or:
Disapprove of PM-most-Don't support increase to the income tax
Theresa Ð Supports increase to the income tax
Therefore: Theresa Ð Probably approves of PM

So the argument tries to take a contrapositive of a most statement—which isn't logically valid. So the correct answer should follow the same pattern, and we can look for the "most" premise and "probably" conclusion to try to make some quick eliminations (which, sadly, doesn't pan out in this question).

Answer Explanation:
This answer choice establishes a trait of most members of a group, and then discusses someone who doesn't share the trait, concluding they probably aren't in the group. That's the same flawed logic as the stimulus, so this is the correct answer.

Key Takeaway:
First, note quantifier language in the stimulus of Flawed/Parallel Reasoning questions. It will usually help you make eliminations, even if it didn't here.

Second, always track groups in these questions. Here, noting how the initially defined group tracked through the argument (from the group where most had a trait to a conclusion where a specific person wasn't a member of it) allowed us to quickly eliminate most incorrect answers.

Incorrect. In this argument, the premise establishes that Bonita isn't in the relevant group, not that she doesn't have a trait present in most of that group, so this answer has different flawed logic.

Incorrect. Similar to (B), this answer establishes that Chung isn't in the relevant group, not that he doesn't have the trait present in most of that group.

Incorrect. Donna is a member of the relevant group, so this answer doesn't commit the same flaw as the stimulus. (In fact, it's arguably valid.)

Incorrect. Edward is a member of the relevant group, so this answer doesn't commit the same flaw as the stimulus. (This argument is flawed because of the jump between people believing a weather report and people seeing it—you could believe a weather report you didn't see because a friend told you about it!)