Logical reasoning PrepTest 129 · Section 3 · Question 20

Incorrect. Calculators → Computers
Computers → Devices for automated reasoning
Devices for automa- and we should stop. This is presenting the necessary condition of one of the conditional premises as part of the some statement, whereas the stimulus had it as the sufficient condition.

Incorrect. Exercise → Beneficial
Beneficial → Promote health
Beneficial-some-not Exercise
Therefore: Exer- and it's time to eliminate this answer. To match, the conclusion would have to talk about some things that aren't exercise—not A in our generic form.

Incorrect. Metaphors → Comparisons

Now don't eliminate this answer too soon! Even though the second premise in order is a some statement, the order doesn't have to match, just the flow of logic. It goes on to present a second conditional, so let's diagram that next so that our order matches the stimulus:

Metapho- and now we stop. The two conditional premises have a shared sufficient condition, whereas they chained together in the stimulus.

Incorrect. Architecture → Design
Design → Art
Design-some-not Architecture
Art-some-not Des- and we're out, as this second term in the conclusion should be not A in our generic form, which maps to not Architecture.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Valid

Question Type:
Parallel Reasoning

Stimulus Summary:
Moral Action → Keeping an agreement
Keeping an agreement → Securing mutual benefit
Keeping an agreement-some-not Moral Action
Therefore: Securing mutual benefit-some-not Moral action

Strategy Overview:
The correct answer choice exhibits the same method of reasoning as the argument in the stimulus.

Answer Anticipation:
Usually, when we see conditional statements mixed with quantifiers in a stimulus, we can rule out some answers because the quantifiers don't line up in the answer choices. However, looking at this set of answers quickly shows us that we're not going to be so lucky here—the answers all line up. Instead, we're going to have to make sure that the terms line up.

So we have:
A → B
B → C
B-some-not A
Therefore: C-some-not A

You can worry about the validity if you want (it's valid), but lining up the terms will ensure that the validity matches the stimulus, so there's no particular need to do so!

Answer Explanation:
Book → Text
Text → Document
Text-some-not Book
Document-some-not Book
A perfect match!

Key Takeaway:
Normally, quantifiers provide an easy way to eliminate some answers. However, when they don't, and the argument is steeped in conditionals and quantifiers, you're in for the long haul—lots of diagramming answers to see if they match. However, don't feel the need to diagram out the entire answer—as soon as you see a mismatch, it's time to bail! With one important note—the order of the premises/conclusion may not line up, so make sure that there's no statement from the original that the part of the answer you're analyzing lines up with.