Logical reasoning PrepTest 131 · Section 1 · Question 21

Incorrect. The stimulus discusses the sliding glass doors being open "intensif[ying]" the effect if it already exists, so it must be possible for the effect to exist with closed doors. The garden contributing a visual interest is only known to apply in the winter months. This answer, therefore, isn't supported by the stimulus.

Incorrect. The garden being coordinated with the room is established as a sufficient condition for the effect to be present, so this answer about when it isn't well coordinated is an illegal negation (or an illegal reversal, if you diagrammed the "unless" term as the necessary condition).

Incorrect. The sliding doors being open (as may happen in summer) was established as a sufficient condition for the effect, not a necessary one, so this answer is incorrect in saying that the open doors are necessary for the effect in summer.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
(1) Garden/living room separated by sliding glass door → Visually merge into single space
(2) Sliding glass door open AND Effect doesn't exist → Effect created
(3) Sliding glass door open AND Effect does exist → Effect intensified
(4) Colder months AND Garden coordinated and interesting → Effect still quite strong

Answer Anticipation:
These conditionals are a mess. There's no clear overlap between them, and the terms are complicated. Let's work through each one to make sure we understand it, and then head to the answers to see if we can support it based on the conditionals.

The first conditional is probably the most straightforward—just an if/then statement ("Any" being equivalent to "If"), so not much to discuss here.

The second conditional is very complex, and it's actually easiest to break it into two conditions since it includes information about two incompatible situations—when the effect doesn't exist, and when it does. Both conditionals are predicated on the sliding glass door being open (we left out the info about summer because it states that the door being open may happen in summer, but that's true with or without stating it, and it doesn't set it up as a sufficient or necessary condition because of that weak language), so the two conditionals start with that term. Then, we break up the two incompatible sufficient conditions (effect existing and not existing), and the outcomes from each.

Finally, the last conditional. The entire statement is predicated on it being the colder months, and then it adds in the condition about the garden. If the garden is coordinated, then the effect is still quite strong. Note that by writing it out this way (with the colder months being sufficient, not necessary), we leave open the possibility for the effect to be strong in other months, which we know to be the case. If we had set it up as necessary, then the colder months would be a requirement for the garden to be coordinated, which isn't what that statement is saying.

Now that we have those statements explained, and we know that combining them is going to be complicated, we should head to the answers and see if we can support them instead of trying to anticipate something specific—it'd be a shot in the dark as far as getting the right anticipation because of the complexity of these statements.

Answer Explanation:
The strong visual interest of the garden by itself was established as a sufficient condition in the winter. This answer choice, rephrased into the language of conditional logic, states that a garden contributing strong visual interest of its own isn't necessary for the visual merging effect to be present. ("Even if X doesn't happen" is a way of saying that X isn't necessary.) Since we have a sufficient condition for the creation of the effect that doesn't include a garden with its own visual interest (adjacency with the door open), it must be the case that that visual interest isn't necessary for the effect, so this answer is supported.

Key Takeaway:
First, when you have a bunch of complex conditionals without any clear chaining opportunities, slow down to diagram them correctly, but then head straight to the answers and compare them to these statements. Second, "Even if X doesn't happen," is a fancy way of saying, "X isn't necessary."

Incorrect. The sufficient condition in that second sentence is that the sliding doors are open. While the stimulus notes this may happen in summer, it doesn't establish that as necessary or sufficient in that clause ("may" being less than certain, so not conditional), and so this answer is incorrect.