We should recognize this as a must be true question, as it asks: If the statements above are true, which one of the following must also be true of trees in the Centerville Botanical Gardens?

This is a stimulus full of comparisons and conditionals. The first sentence gives us a conditional indicated by all, which tells us that if you are tulip trees, then you are older than all the maples. Next, we learn that most, but not all, of the sycamores are also older than all the maples. The last sentence gives us our final conditional that if you are a maple, then you are older than all the dogwoods. Interesting! I think it can be helpful to use some of our sequencing game skills here, and remember that if A is before B, and B is before C, then A is before C. In this case, we are getting a lot of comparison of tree ages, and should think about how they can chain together; I’d expect that the correct answer will be an inference from chaining together these comparisons. Specifically we can form a chain (T AND (most)S → older than M → older than D) from which we can infer that all the tulip trees and most of the sycamores are older than all the dogwoods. Let’s see if this ends up being useful in the answer choices.

Answer Choice (A) This must be false, as we’ve been told all tulips are older than all maples which are older than all dogwoods.

Answer Choice (B) This could be false, as we’ve only been told about the age of the majority of sycamores.

Answer Choice (C) Same as C, we don’t know enough for this to be a certain inference

Answer Choice (D) This could be false as, although we know that some sycamores and all tulips are both older than all maples, we don’t know how the ages of these two groups compare.

Correct Answer Choice (E) Since we’ve been told that not all sycamores are older than all maples, but all tulip trees are, then there must be some sycamores that are younger than all tulip trees.


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We have a must be true question here, as the stem demands: If the statements above are true, which one of the following must on the basis of them be true of woolly monkeys in colonies?

This is a very short, straightforward stimulus. Our first sentence begins with the conditional indicator every. If we translate this first conditional, we should see that just being an adult male woolly monkey is enough to be larger than all female woolly monkeys. Our second sentence adds on to this information with another conditional, indicated by the sufficiency indicator any. From this we learn that an adult male woolly monkey is capable of dominating all females. Ok, so the adult males are always larger than and capable of dominating the females, got it. Since this is a must be true question and all our stimulus gives us is two conditionals which cannot be chained, we should expect the inference will either involve a contrapositive or a simple triggering of one of the conditionals leading to its necessary condition. Let’s see what we get.

Answer Choice (A) This answer might be appealing because there seems to be a strong correlation between the men being all larger than the females and all capable of dominating them, but this inference requires that we assume this correlation entails that size is the primary determinant, and there aren’t any other possible determinants which we just haven’t heard about. A must be true inference will never require an assumption.

Answer Choice (B) Our rules have only been about adult males, we can’t infer anything about the adolescents with certainty.

Answer Choice (C) Again we have to read carefully here; we only know about specifically adult males, so we can’t infer this general rule about all males. What if some adolescent males are larger than females but won’t dominate them yet.

Correct Answer Choice (D) This is just the contrapositive of our second rule. If a male doesn’t dominate a female, then the male must not be an adult male.

Answer Choice (E) This must be false, as we’ve been told any adult male will dominate any female; this answer choice would entail that adult males won’t dominate some females.


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We can identify this question as Method of Reasoning because of the question stem: “In countering the original conclusion the reasoning above uses which one of the following techniques?”

When dealing with a Method of Reasoning question, we know we are looking for an answer choice that correctly describes the structure of our entire argument. Our correct answer is going to fit the argument exactly. Our wrong answer choices likely explain argument structures we are familiar with, but that simply don’t apply to the specific question we are looking at. Knowing what the right and wrong answers are going to do, we can jump into the stimulus.

The argument begins by telling us about a correlation; those who play bridge tend to have better short-term memories than those who do not play bridge. We know right away that the presence of two qualities at the same time does not mean they caused each other. The argument proceeds by affirming this exactly. We are told that although this correlation was previously concluded to indicate a causal relationship meaning bridge causes better short-term memory, it is just as likely that having a better short-term memory makes the game of bridge more intriguing to that particular group of people.

Ultimately, our stimulus outlines an incorrect conclusion on the basis of a correlation and then goes on to explain another possible interpretation from the evidence. Knowing this, we can jump into answer choice elimination.

Answer Choice (A) If our stimulus were challenging the representativeness of the study included, we would expect the argument to bring up the number of people involved in these different groups or how well these groups represent the rest of the population. Without this information we can eliminate answer choice A.

Answer Choice (B) This answer accuses our stimulus of drawing a conclusion about what is considered “appropriate therapy.” Without this emphasis in the text we can eliminate B.

Answer Choice (C) Our stimulus does not depend on some sort of misunderstanding of the facts involved in the scenario. Thus, we can nix answer choice C.

Correct Answer Choice (D) This is exactly what we are looking for! This is the only answer choice that identifies the alternative possible explanations for the facts presented in the argument.

Answer Choice (E) This answer choice is tricky. But our stimulus does not go quite far enough to say it is describing a flaw of the previous conclusion. Because our stimulus only points out the existence of another possible conclusion we cannot confirm answer choice E.


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We can identify this question as Method of Reasoning because of the question stem: “Jonathan uses which one of the following techniques in his response to Lydia?”

When dealing with a Method of Reasoning question, we know we are looking for an answer choice that correctly describes the structure of our entire argument. Our correct answer is going to fit the argument exactly. Our wrong answer choices likely explain argument structures we are familiar with, but that simply don’t apply to the specific question we are looking at. Knowing what the right and wrong answers are going to do, we can jump into the stimulus.

Immediately we should make note of the two speakers at play. This means we could possibly be dealing with two different conclusions with different levels of support. Our first speaker, Lydia, tells us seabirds often become entangled in equipment owned by fishing companies. Lydia concludes on the basis of this that the fishing companies should assume responsibility for the medical treatment of these animals.

Lydia’s position makes an assumption here. If our conclusion tells us that something should happen, our evidence needs to give us reasoning to guarantee the outcome should occur. Perhaps, for instance, there is a law indicating those causing harm to animals should be responsible for them. But without this information the evidence does not automatically lead to the conclusion that the fisherman should be responsible for anything.

Jonathan does not quite hit the assumption out of the ballpark. In response, our second speaker concludes the proposal should not be adopted because the most injured birds won’t be able to return to the wild. Remind yourself here of how uncertain the number of “most injured birds” is. Perhaps 99.99% of the birds are injured mildly and 0.01% are the “most injured” with extensive injuries. Putting things into context, Jonathon’s response asking us to consider a group that could be impossibly small and irrelevant to Lydia’s ultimate conclusion.

Knowing that we are looking for an answer choice that will highlight Jonathon’s use of a small subset of these animals in a (poor) attempt to weaken Lydia’s reasoning we can jump into answer choice elimination.

Answer Choice (A) This answer choice accuses Lydia of a personal attack. But without any reference to Lydia’s motivation or other personal characteristics, we have to eliminate this answer from contention.

Answer Choice (B) We can eliminate this answer for a similar reason why we eliminated answer choice A. Like a personal attack, B accuses Lydia of being wrapped up in their personal interests - an attack we do not see used as the reasoning for Jonathon’s conclusion.

Answer Choice (C) This answer choice goes too far in the extreme. By accusing our second speaker of not wanting to interfere with wildlife in any way, this answer choice claims Jonathon’s conclusion goes even further than we can see in the stimulus.

Correct Answer Choice (D) This is exactly the answer we are looking for! This is the only answer choice that references Jonathon’s use of the sickest group of birds in an attempt to weaken Lydia’s argument.

Answer Choice (E) While Lydia’s feelings are addressed at the beginning of Jonathan’s argument, this is not the reasoning used to prove Jonathon’s main point. They claim we should not adopt the proposal because of this sub-group of birds. Not because of Lydia’s personal feelings in the matter.


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