This is a necessary assumption question; we know this because the question stem says: “… following assumption on which the consumer activist’s argument depends?”
Necessary assumption questions fall under the umbrella of the strengthening subset of questions. The analysis of the stimulus is the same. However, our approach changes with our answer choices. Where we were trying to find an answer choice that justified our argument in strengthen, pseudo-sufficient/sufficient assumption questions, the purpose of a necessary assumption correct answer choice is very different. We’re trying to find what is necessary for our argument. In other words, in order for our conclusion to be true/for our argument to work, the correct answer choice must be true.
On the old LSAT, the test would give us one stimulus for 2 questions. Unfortunately, that is no longer the case – the LSAT will definitely give us 25-26 different stimuli for us to get this. Question 17 was a NA question that required us to read both blurbs. For this question, we can ignore the “industry representative” blurb.
The activist’s claim is a single sentence. There is a lot of information packed in here, so let’s break this up by commas starting by reading up until the third comma. We know that airlines were allowed to (and did) abandon all of the routes except their most profitable routes. By whom were they allowed to do this? We don’t know yet.
If we read on, we’re told that the “government’s decision to cease regulation…” What decision are they referring to? Well, it must be their decision to let airlines choose their routes. We’re told that this decision has worked to disadvantage everyone who can’t get to major airports, presumably because this is where all of the “profitable” routes go through.
The first half of the sentence provides support for the second half. The premise is that because the government allowed airlines to abandon whatever routes, the government’s decision hurt certain people. This seems fine at a surface level, but there is a very subtle gap here. There is a correlative-causal element. The argument correlates the timing of the government’s decision to the timing of airlines abandoning routes, and then assigning blame to the governments for the airlines’ actions in the conclusion. Because of the government’s decision, people are disadvantaged. Remember, in the core curriculum correlation does not imply causation (lesson linked here). The airlines could have just decided to do whatever they wanted, regardless of what the government said.
There could be many necessary assumptions for this argument. In order for the causal conclusion to be true, one necessary assumption is affirming that the causal connection exists.
Answer Choice (A) While the argument does talk about advantages in the conclusion, whether or not there was an advantage of easy access before the decision is not necessary for the conclusion or the argument. A change in the ease of access to large metropolitan airports is not necessary for the argument either. This is out.
Answer Choice (B) A change should be reversed? Our conclusion does not hinge on a prescriptive statement. This is not necessary for our conclusion to be true.
Answer Choice (C) Must this answer choice be true in order for our conclusion to be true? No! “Almost always” could be changed to “rarely” and our argument would still stand. This isn’t necessary.
Correct Answer Choice (D) This addresses the correlation-causal element we discussed above and affirmed a partial causal relationship. If we negate this relationship (instead of “at least in part” we get “no part”) this would destroy the argument.
Answer Choice (E) This is not necessary for the conclusion to be true. Regional airlines could have excellent customer service without the reach/routes of major airlines.
This is a Sufficient Assumption (SA) question and we know this before the question stem: “… an assumption that would allow the company president’s conclusion to be properly drawn?”
Sufficient assumption questions tend to be very formal. We’re looking for a rule that would validate the conclusion, specifically by bridging the premise and conclusion through the rule. Not only are we extrapolating the rule from our argument, but we’re also using that rule to render the argument “valid.” The way to prephrase our answer choice is by tying our premises and conclusion together into a rule: “If [premise] à then [conclusion].” In this question, this isn’t really the case.
In our first sentence, we’re told that Wilson gives free merch to its top salespeople. We’re not told how the company defines “top salespeople” or how many of them there are.
Next, we’re told that the number of salespeople getting this award has declined a lot over the past 15 years. In response to this, the president of Wilsons says: since our award standard is being a part of the top third of the sales team, we can also conclude that the number of people being passed over for awards has declined.
There is a lot of information in the passage and a couple of assumptions the president is making in his argument. It’s easiest to understand this if we put it into perspective if we have some numbers attached to this.
Fifteen years ago, let’s say in 2000, 100 people were given the award.
Now, in 2015, markedly fewer people got the award. Let’s say 50 people got the award. Based on what the president says, the criteria for awarding the prize is being a part of the top third of the sales force. So, if 50 people are 1/3 of the total sales force, the total sales force would be equal to 150 people. This means that 100 people were NOT awarded. Great!
The only problem is: do we the people who were NOT given an award in 2000? No! How do we know that in 2000, the award criteria is being part of the top 2/3 of the sales force? This would mean that the total sales force was 150, and 50 people were NOT awarded. That would really go against the conclusion.
The president is assuming that because there is a decrease in the awarded, there is a decrease in the NOT awarded. What must we have to guarantee that this is not the case? Membership of one-third OR LESS of the sales force would qualify salespeople for the award. This is our rule.
Answer Choice (A) Hiring policies being the same doesn’t mean anything for the number of people employed OR the number of people passed over for the award. It could be that more people are seeking jobs now than before or vice versa. There are so many ways this could affect the number of people employed and passed over for an award, but no way does it allow us to conclude that the number of people passed over for an award has decreased.
Answer Choice (B) Just because the number of salespeople has increased, that does not mean that the number of people of passed over for an award was higher than 15 years ago. We don’t know the criteria for awards back then, so we can’t draw a conclusion about the people awarded vs not awarded.
Correct Answer Choice (C) It gives us that missing information on the proportion of awardees to the total number of employees, allowing us to conclude that the number of people not awarded has also gone down.
Answer Choice (D) If we plug this back into our stimulus, does this validate our conclusion? No! If sales figures are declining, there could be a number of reasons why, and none of this helps explain why the president is able to conclude that non-awardee numbers have also gone down.
Answer Choice (E) We’re not concerned about calculating sales figures. If this is true, and we have different selection criteria, the number of people passed over for an award could increase or decrease. This does not help validate our conclusion.
This is a sufficient assumption question because of the question stem: “Which one of the following, if established, would help justify…” Note that there are two speakers; we’re specifically focused on validating Oscar’s argument.
Sufficient assumption questions tend to be very formal. We’re looking for a rule that would 100% validate the conclusion, specifically by bridging the premise and conclusion through the rule. Not only are we extrapolating the rule from our argument, but we’re also using that rule to render the argument “valid.” The way to prephrase our answer choice is by tying our premises and conclusion together into a rule: “If [premise] → then [conclusion].”
Oscar’s argument is given first. He’s being accused of plagiarizing the work of Myers but says it is unwarranted. What reason does he give for this? Why should we believe him? He first gives a concession: he used Myer’s work without attribution. Even though this is the case, he didn’t plagiarize because Myer gave him permission for this. So, the conclusion of Oscar’s argument is that the accusation that he’s guilty of plagiarism is unwarranted, and his premise is that he got permission in private correspondence to do use Myer’s work without attribution.
Millie’s argument is basically trying to weaken Oscar’s argument. We know this stimulus is for two different questions, so it’s like that question 6 has something to do with both of the speakers. On the older LSAT, it was very common for the test to give one stimulus for two different questions; this doesn’t happen anymore. We can basically ignore Millie’s claim because we’re trying to validate Oscar’s position. If you do end up reading it, the position Millie takes uncovers a useful implicit assumption that Oscar is making.
Back to the Oscar’s argument: does getting permission from the author to use their work without attribution exclude you from plagiarism? Do we know this from the information in our stimulus? No! This is the implicit assumption that Oscar is making. (This also happens to be the implicit assumption that Millie targets to weaken Oscar’s position). In order for this conclusion to be true, our rule would need to look something like “If I get permission in personal/private correspondence from the author to use their work without attribute, then I’m not guilty of plagiarizing.”
Answer Choice (A) This is one of the ways in which LSAT will routinely trick you – switching the sufficient and necessary conditions. Another way the LSAT will trick you is by putting the sufficient condition later in the sentence and putting the necessary condition first. Notice the “If” later on in the sentence; everything after that is our sufficient condition. With our rule, the direction of the conditional matters. This answer choice has “no right to quote” in the necessary condition, but we want “right to quote” or “not plagiarism.” We can also look at the sufficient condition: we’re looking for getting permission and our answer choice says, “the author hasn’t grant author any right.” This is out.
Answer Choice (B) This is another conditional in which the LSAT has put the sufficient condition later on in the sentence. Rearranged, it reads: “If the quote is more than a few sentences long, the writer of an article must attribute the text.” We can’t even satisfy the sufficient condition to trigger the conditional because we do not know how much Oscar pulled from Myer’s book. In addition, even if we could assume it’s just a few sentences, this would actually weaken the argument. This is also out.
Answer Choice (C) This isn’t correct: we start out we a blanket statement: “Plagiarism is never justified.” But then the answer gives us an exception: “but writers are justified in occasionally quoting without attribution…” Stop here. What would it need to be for this to be the correct answer choice? “When the author gives permission to use their writing without attribution.” That would be great! What does our answer choice say? “If the work has not been published.” This does not apply to our stimulus because we don’t know if it hasn’t/has been published.
Correct Answer Choice (D) The necessary condition is presented first, so if we rearrange the order, we get: “if a writer relinquishes their exclusive right to their work, then another author is entitled to quote freely without attribution.” The “relinquished their exclusive right” is a little dramatic and fancy but saying in private correspondence that someone else can use their work without attribution is relinquishing an exclusive right.
Answer Choice (E) “Quote without attribution what they themselves have written” is the problem here. We’re not talking about what Oscar quotes from his own work; he’s quoting another author. This is out.
This is a sufficient assumption question because of the question stem: “…conclusion would be properly drawn if it were true that…” Note that there are two speakers in this stimulus – our job is to address the missing SA in the environmentalist’s argument, but since the environmentalist is responding to the oil rep, we must read both blurbs.
Sufficient assumption questions tend to be very formal. We’re looking for a rule that would 100% validate the conclusion, specifically by bridging the premise and conclusion through the rule. Not only are we extrapolating the rule from our argument, but we’re also using that rule to render the argument “valid.” The way to prephrase our answer choice is by tying our premises and conclusion together into a rule: “If [premise] → then [conclusion].”
The oil company rep’s argument is pretty straightforward: we spent more money cleaning otters hurt by the spill than any other rescue project we’ve been involved in, and this shows their concern. While it’s straightforward, it’s not a solid argument. There are many reasons they could have spent the money… maybe it was a PR move and they have no real concern for the otters.
We’re given the environmentalist’s (E) thoughts on this immediately: they do not believe the rep from the oil company. Why? E says that the rep’s real concern is clear in their admission that photography of the oil-covered otters would damage the oil company’s public image and sales.
E’s argument could definitely weaken and call into question the true motive of the oil company’s motive in trying to help the otters – as we said above, it would be a PR move. However, to claim that the oil company has no concern for the environment is wrong given the information we currently have. Can’t the oil company care about its public image and the environment? E is assuming that if the company has other reasons to help the otters beyond saving the environment, the concern is not real. What we need to bridge the gap and render E’s conclusion valid is to say: if you have any motive beyond saving the environment, your concern is not real.
Correct Answer Choice (A) While it’s not a perfect match to our prephrase, it does get at the “you can’t have both/you can only have one reason” language. This answer choice works because we already know they admitted to cleaning the otters because photography of them covered in oil would have damaged the company’s image and sales. If that’s a reason and we plug A into E’s premises, then the oil company rep’s claim is thrown out the window.
Answer Choice (B) This is not correct – it doesn’t matter that they were saved by the rescue project, nor do we care about the results. We care about the motive for the project.
Answer Choice (C) This is not correct and doesn’t do anything to help the conclusion. This is just adding more information about how important sales are to the company, but they could just as equally have concern for the environment.
Answer Choice (D) This information is irrelevant to the premise and conclusion. Just because the government would have helped, doesn’t mean that the oil company’s concerns aren’t actually for the environment.
Answer Choice (E) This answer choice is saying that the rescue project was more successful than any other of their projects – but that has nothing to do with their motives. This is wrong.
This is a Sufficient Assumption (SA) question and we know this because of the question stem: “… an assumption that would make the conclusion in the passage a logical one?”
Sufficient assumption questions tend to be very formal. We’re looking for a rule that would validate (not just strengthen) the conclusion, specifically by bridging the premise and conclusion through the rule. Not only are we extrapolating the rule from our argument, but we’re also using that rule to render the argument “valid.” The way to prephrase our answer choice is by tying our premises and conclusion together into a rule: “If [premise] à then [conclusion].”
Our first sentence is describing how some accountants use adding machines while some use computers. I can’t give examples of the two, but it doesn’t matter. If it did, the stimulus would specify. What is important about the difference between the two is given in the next sentence: complex computers are faster than adding machines: they’re efficient compared to adding machines as we can do more in less time. So far, this makes sense.
The next sentence begins with a conclusion indicator. I haven’t seen anything that looks like a conclusion, but let’s read the whole sentence before we put labels on anything. The author explicitly assumes that the costs of the two machines are equal and then claims that accountants who use complex computers earn more per hour than accountants who use adding machines.
Hang on a minute – there’s a huge gap here between doing more calculations per hour and earning more per hour. These two things aren’t necessarily related. What if they work on salary and their bonuses do not depend on how much work they do? What if they only get a fixed number of clients and finishing work sooner rather than later has no bearing on how much they will earn?
If order to bridge this gap in our prephrase, we can simply say something like “the more calculations accountants are able to do, the more they can earn.”
Answer Choice (A) This is incorrect. Our rule doesn’t care about the number of accountants that are using the complex machine. The rule wants to address the gap between using the machine and how it affects earnings.
Answer Choice (B) This is close, but it’s wrong. Earnings are affected by the number of calculations one can perform, it’s not about the number of hours. If it was about the number of hours, it would be better to use a slower calculator as it would take more time to do the job.
Correct Answer Choice (C) It’s a paraphrase of our prephrase.
Answer Choice (D) This is not correct because this would weaken the conclusion: they’d be able to charge more using the adding machine and, assuming the price charged is proportional to earnings, they would be able to earn more.
Answer Choice (E) This answer choice establishes a vague relationship between earning and money. It’s not enough. We need a positive relationship between the two.
This is a sufficient assumption question because the question stem says: “conclusion follows logically…if which one… is assumed?”
Sufficient assumption questions tend to be very formal. We’re looking for a rule that would 100% validate the conclusion, specifically by bridging the premise and conclusion through the rule. Not only are we extrapolating the rule from our argument, but we’re also using that rule to render the argument “valid.” The way to prephrase our answer choice is by tying our premises and conclusion together into a rule: “If [premise] → then [conclusion].”
Our first sentence is very straightforward: in bureaucracies, decisions involve many people. The sentence just elaborates on this by saying that no one person have more authority than the next person. These are both our premises.
Our conclusion states that in bureaucracies, risky projects are never undertaken. That’s a big jump! From “bureaucracy decisions involving multiple people” to concluding “risky projects are never undertaken”? What if that is the exact they take on risky projects? For example, they could say that because many people are involved, they’re able to prepare for every outcome.
In order for our conclusion to follow, we need to link up the idea in the premises to the conclusion: when multiple people are involved in decisions and no one has the authority, risky projects will not be taken.
Answer Choice (A) This isn’t correct. We’re trying to make our conclusion about risky projects not being taken on valid; the fact that projects always require risk doesn’t help the gap in our argument.
Answer Choice (B) This isn’t correct either. The gap here is that the argument assumes that have many people involved in a decision means that no risky project will be taken. If we plug this into our stimulus, this doesn’t help validate our conclusion. It could support it, but there are too many assumption we need to make to arrive to our conclusion.
Answer Choice (C) This is more or less what our premises are trying to say, but again, it’s not helping to validate our conclusion about risky project not being taken on in bureaucracies. Additionally, we’re not concerned with what groups of people will take risks - we specifically interested in bureaucracies who will not take risks.
Correct Answer Choice (D) We said we weren’t interested in people who take risks, but this is a conditional statement! The answer choice is saying “when risk take, then single individual power to decide.” Taking the contrapositive of this would be: if multiple people have the power to decide, the risk is not taken. See how “no risk taken” is in the necessary condition? This is the NC in our rule, and it’s also our conclusion. Our premises trigger the contrapositive of this answer and allow us to draw our conclusion.
Answer Choice (E) This isn’t correct; what people do on there own is outside the scope of their decision as a group. This doesn’t help us draw our conclusion.
This is a necessary assumption question because the stem tells us that the argument “depends on the assumption.”
Necessary assumption questions fall under the subset of strengthen questions. All of the things we learned for strengthen, SA, and PSA question are still very important here! We’re going to be analyzing the stimulus the same way: identify the premise and conclusion, evaluate the argument, and determine what is missing. Our approach to the questions is very different. For NA question, in order for our conclusion to be true, our correct answer must be true. Without the correct answer, our argument will fall apart. This is what we’re looking for in our answer choice. Remember, we can always test our answer choices by using the negation test: if we negate the answer choice and it destroys our argument, it is the correct answer!
The first sentence is pretty straight-forward: the permits are issued in terms of pounds of each chemicals that can be dumped into the waterway per day. So, each chemical has a specified weight that can be dumped in the water each day. We’re also told how these numbers are calculated: by looking at the effects dilution in the water based on the amount of water flowing through the waterway. So there’s two variables here: the dilution and how much water passes through the waterway. This makes sense: if you have more/less water flowing through the waterway, dilution will change. Great! The next sentence is the conclusion: based on all of this information, the waterway is protected.
On the LSAT, there is a correct amount of skepticism you need to have. The argument is okay but, while it’s difficult to pinpoint, there is a gap here. A number of things could happen in order for this conclusion to not be true. For example, what if no one follows these guidelines? What if calculation of water flowing through the waterway isn’t accurate because the flow of water changes through the day? Any number of things need to be true if our conclusion, the waterway is protected, is true.
Correct Answer Choice (A) This is necessary for the argument! If, even in safe quantities, chemicals interact to form harmful ones, that would destroy our argument.
Answer Choice (B) Is rapid dispersion necessary? Maybe the flow is very slow, but the amount of chemicals allowed in the waterway is very low. This is not good.
Answer Choice (C) This is also not necessary. Let’s take the negation of this sentence: some chemicals are prohibited from being discharged into the waterway. So, what? Perhaps arsenic isn’t not allowed to be dumped - is that compatible with the argument? Yes! Prohibiting certain chemicals to be dumped in the waterway does not destroy the argument.
Answer Choice (D) This is also not necessary. The permits indicate the max amount that can be dumped into the water, which means dumping anything at the maximum amount or below is fine. Negating this sentence (they dump the full amount indicated by the permit) does not destroy the argument.
Answer Choice (E) This weakens our argument a little bit - it mentions what we’re not taking into consideration in an effort to say that the waterway may not be as protected as the argument says. This is out.
This is a necessary assumption question because the stem tells us that the argument is “depends” of the which of the offered “assumption.”
Necessary assumption questions fall under the subset of strengthen questions. All of the things we learned for strengthen, SA, and PSA question are still very important here! We’re going to be analyzing the stimulus the same way: identify the premise and conclusion, evaluate the argument, determine what, if anything, is missing. Our approach to the questions is very different. For NA question, in order for our conclusion to be true, our correct answer must be true. Without the correct answer, our argument will fall apart. This is what we’re looking for in our answer choice. Remember, we can always test our answer choices by using the negation test: if we negate the answer choice and it destroys our argument, its the correct answer!
This first sentence gives us the definition for addiction and, interestingly, the author uses “has been defined as” which kind of gives us the sense that this may be other people’s definition. This definition is that addiction means the dependence on and abuse of a certain substance. If we read onto the next sentence, even if the “however” is at the end, we can infer that the author does not agree with the running definition of addiction; he says that abuse and dependence do occur together.
The next two sentences are examples of this. He says cancer patients are dependent on morphine, but do not abuse it because they use it for their pain. And then he gives a general example of the reverse: a person can abuse morphine but does not need to dependent on it for anything.
Then we see our conclusion, which we predicted above: this definition of addiction is not correct.
This argument is fine. The salient feature of difficult NA question is that the correct answer choice can be VERY subtle. The negation test will be helpful for these answer choices.
Answer Choice (A) This is not necessary to our argument. Cancer patients could have abused morphine is the past; the argument allows for this! The example in the argument is a hypothetical that can occur. And if we negate the answer choice (cancer patients sometimes abuse morphine), this is completely compatible with the argument because the example with the cancer patient is a hypothetical.
Answer Choice (B) This is not necessary for the argument. This answer choice is trying to draw a distinction between the hypothetical language of the argument and what will happen. However, it is not necessary for all cancer patients to often become dependent on morphine. Similar to what we said in AC (A), cancer patients rarely (instead of often) becoming dependent to morphine and the rest never becoming dependent is compatible with the argument.
Correct Answer Choice (C) When we read the argument, we just assumed that we were obviously talking about cancer patients who were addicted to morphine. But, we did not explicitly say that. If we negate this answer choice, it destroys our argument because the example we give to lend support to our argument becomes useless if the cancer patients are not addicted. In other words, if the individuals discussed in our examples are just dependent on or abusing a substance and not addicted, our argument falls apart. Very subtle!
Answer Choice (D) Similar to (A) and (B), this is not necessary for the argument. It could be the case that some cancer patients are just abusing the drug without being dependent on it. The negation of this doesn’t destroy our argument.
Answer Choice (E) This would weaken our argument; we’re trying to prove that abuse and dependence can happen separately while being addicted.
This is a necessary assumption question and the stem asks: the argument is based on which one of the following assumptions?
The first sentence asks as a concession to the opposing side: as subsidies go down, it’s obviously very hard to maintain the quality of service. In the next sentence, we see an important “pivoting” word: however. This sentence is saying that even though we have less money, the amount of passengers riding has gone up. The next sentence is the conclusion and the “this fact” at the beginning of the sentence refers to the sentence right before it about the number of riders increasing. The conclusion is that their quality of service has been satisfactory. So, even though they have less money, riders are still riding. From this much, doesn’t our conclusion seem like a bit of a stretch? For example, let’s pretend that the NYC subway system is getting less and less money every year. Do you think New Yorkers will ride the train because the quality of service is fine or because they may not have any other choice? The former could be true, but the latter is more likely to be true. Now, we’re not trying to weaken the argument, but this level of analysis is still very important.
Answer Choice (A) This answer choice is pointing out the wishes of taxpayers. The argument does not depend on what taxpayers wish. If we negate this, it doesn’t do anything to the argument.
Correct Answer Choice (B) This is conditional language - do you see the “some” and the “if”? This is a “some” conditional, so we can flip the NC and SC as we please, but let’s flip these two. If some people are dissatisfied with the service, they will not ride the train. Remember what our argument is: people are riding the subway regardless of the reduction in subsidy, therefore they must be satisfied. Does our argument depend on this? Absolutely. Let’s negate it to check: if some people were dissatisfied with the service, they would still take the train. That destroys our argument.
Answer Choice (C) This is an attractive answer choice, but is improvement necessary to the argument? No! The riders could be totally okay with the way the train is now, and that’s why they’re satisfied with the service.
Answer Choice (D) This answer choice is incorrect for similar reasons to the answer choice above. Is a decrease in quality of service necessary for satisfaction with the service? No! What if they’re still satisfied even if the quality of service went down just a little bit? That would not affect the argument at all.
Answer Choice (E) This answer choice is noting that even though the subsidy itself was decreased, the revenue will offset the reduction. Is this necessary for our argument that the passengers are satisfied? No! Would this be nice to have, sure; however, even if this didn’t happen, our argument would be intact.