Logical reasoning PrepTest 139 · Section 4 · Question 6

Incorrect. This answer fails to establish that Simkins' membership on the committee isn't supported by all members of the board, so it misses one of the two joint sufficient conditions.

Incorrect. The Principle addresses first-term board members, so it doesn't apply to Timmons since he's a third-termer.

Incorrect. While you might be inclined to take the contrapositive of the conditional Principle to see if this answer is justified, don't! The Principle is about whether someone should be on the board, not whether they are, so this answer is out of scope.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True (Principle)

Stimulus Summary:
not Accountant AND not Membership supported by all members → 1st-term board member shouldn't be on finance committee

Answer Anticipation:
For Must Be True (Principle) questions, the principle will almost always be stated as a conditional statement (in fact, there will frequently be two conditional statements to work with). We should work to get the "judgment" in the necessary condition, allowing that judgment to be reached as a conclusion.

Here, the judgment is about what "should not" happen, so we want to ensure that's the necessary condition with a sufficient condition that can justify it. We diagrammed the statement treating "unless" as "if not," so if you ended up with the contrapositive of our principle, that's fine, too—you'd just need to take the contrapositive to get the "should not" statement as the necessary condition.

Note that the stimulus has the "unless" clause as an OR statements, but we diagrammed it as AND. That's because, when treating "unless" as "if not," you need to apply the negation (if not) to the entire clause—including any connectors such as AND and OR.

To highlight this, let's look at a more straightforward example—You can't afford the new video game unless you have $60 or store credit. It wouldn't make sense to diagram this as (not $60 OR not Store credit → not Video game) because not having $60 doesn't guarantee you can't get the game—you still might have store credit. Instead, not having $60 and also not having store credit would guarantee you can't get the game, thus making it an AND statement. When treating "unless" as "if not," don't forget to negate any connectors!

With that established, we can head into the answer choices to find one that establishes a situation where someone isn't an accountant and whose membership isn't supported by all board members, concluding that they shouldn't be on the finance committee.

Answer Explanation:
This answer reflects the Principle. Klein is a first-term board member, so the Principle applies to her. She's not an accountant, meeting one of the sufficient conditions. Thus, if she meets the other—she doesn't have unanimous board approval—then she shouldn't be on the board, as this answer states.

Key Takeaway:
Must Be True (Principle) questions will generally provide a conditional. If you get the diagram down, you're most of the way to finding the correct answer—compare the details of each to see if it establishes the sufficient condition in reaching the necessary condition.

Incorrect. This answer doesn't establish Mabry's tenure, so we don't know if he's a first-termer and thus if the Principle applies.