Logical reasoning PrepTest 125 · Section 4 · Question 25

Incorrect. The second conditional here has an AND sufficient condition, and it doesn't bring in a new term the way that the stimulus does, instead relating the necessary conditions to each other. Therefore, we can eliminate it.

Incorrect. This answer has the AND and OR conditions, so we need to diagram it out:
Class president → Well liked AND Well known
Well liked OR Well known → Better to do than run for president
Therefore - Better to do than . . . If you diagram this conclusion correctly, it has the necessary condition of the second conditionals as its sufficient condition. That's an illegal reversal, so it's not parallel to the stimulus.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Valid

Question Type:
Parallel Reasoning

Stimulus Summary:
Free dessert → Entree AND Salad
Entree OR Salad → Free soft drink
Therefore - not Free soft drink → not Free dessert

Answer Anticipation:
This Parallel Reasoning question seems like it could take a while, but there are some indications in the stimulus that we may be able to find the correct answer quickly.

First, it's conditional ("must", "either. . . or", "anyone"), so we can diagram it out and find the answer from there. Second, there are complex conditions—both AND and OR statements. We can look to match those in the correct answer, and we can eliminate answers that don't have similar conditions.

So we're looking for an answer that takes the following form:
A → B AND C
B OR C → D
Therefore - not D → not A

One more note—since any answer that aligns with this structure will be correct, we don't need to consider the validity of this argument. However, just FYI, this is a valid argument. Since A guarantees both B and C, the sufficient condition of the second conditional is triggered—either B or C individually would be sufficient, so both are also sufficient. If the order were reversed—the necessary condition of the first conditional as an OR and the sufficient of the second as an AND—then this wouldn't be valid.

Answer Explanation:
This answer has the AND and OR conditions, so we need to diagram it out:
Good azaleas → Rich humus soil AND Low acidity soil
Rich humus soil OR Low acidity soil → Grow blueberries
Therefore - not Grow blueberries → not Good azaleas
This matches the stimulus, so this is the correct answer.

Key Takeaway:
While complex conditional statements can be annoying to work with, they're great for Parallel Reasoning questions. Since those complex elements need to match in the correct answer, a lot of answers can be quickly eliminated for missing those features.

Incorrect. The necessary condition of the first sentence here is an OR statement, so it's not parallel to the stimulus where the OR condition is in the sufficient condition.

Incorrect. This answer has the AND and OR conditions, so we need to diagram it out:
Ice cream discount → Buy frozen raspberries AND Buy ice cream (together)
Buy raspberries OR Buy ice cream → Coupon for later purchase
Therefore - not Ice cream discount . . . and we can eliminate this, as it negates the sufficient condition of the first conditional. That means there's an illegal negation here that isn't present in the stimulus.