Summary
A few years ago, some Hollyville residents helped send aid to victims of an earthquake. Last year, Hollyville was hit by a tornado and received aid from others. This year, after a flood hit a different town, most Hollyville residents sent aid to that town. The proportion of Hollyville residents who sent aid this year was much higher than the proportion that sent aid a few years ago, before Hollyville itself had been hit by a natural disaster.
Strongly Supported Conclusions
Hollyville’s receipt of aid after a tornado may have increased the proportion of Hollyville residents willing to donate to others after a natural disaster.
A
People are more likely to aid people they know than they are to aid strangers.
Unsupported. We don’t know whether any of the recipients of aid were known or strangers to the people who gave the aid. So there’s no evidence that people are more likely to aid people they know.
B
Those who have received aid are more likely to be in favor of government relief programs than are those who have not.
Unsupported. The stimulus never mentions government relief programs or whether Hollyville residents became more likely to support such programs after receiving aid.
C
The amount of aid that victims of a disaster receive is unrelated to the extent to which the disaster is publicized.
Unsupported. We don’t know the amount of aid anyone received or its relationship to the level of publicity. Although we know about the proportion of Hollyville residents who donated, that doesn’t tell us about the amount of aid received by the people to whom Hollyville donated.
D
Once a disaster has struck them, people are more likely to aid others in need than they were before the disaster.
Strongly supported. A higher proportion of Hollyville residents donated this year compared to a few years ago after Hollyville was hit by a natural disaster (tornado) last year and received aid from others.
E
People are more likely to aid those who have experienced a hardship similar to one they themselves have experienced than to aid those who have experienced a dissimilar hardship.
Unsupported. Hollyville experienced a tornado. Other towns experienced an earthquake and flooding. There’s no basis to say that a tornado is more similar to what Hollyville experienced than is an earthquake.
Market analyst: According to my research, 59 percent of consumers anticipate paying off their credit card balances in full before interest charges start to accrue, intending to use the cards only to avoid carrying cash and writing checks. This research also suggests that in trying to win business from their competitors, credit card companies tend to concentrate on improving the services their customers are the most interested in. Therefore, my research would lead us to expect that _______.
Summary
The market analyst's research indicates that over half of consumers plan to pay off their credit card balances in full before interest charges accrue. The research also suggests that credit card companies, in an effort to compete, focus on improving the services their customers care about most.
Strongly Supported Conclusions
Credit card companies do not focus on interest rates as one of their main selling points.
A
most consumers would be indifferent about which company’s credit card they use
This is too strong to support. The stimulus only says that most consumers intend to pay off their account balance before interest starts to accrue. Even if you read this as being “indifferent,” you have to assume that the interest rate is the only factor consumers care about.
B
credit card companies would not make the interest rates they charge on cards the main selling point
Most consumers do not intend to make late payments with interest. The stimulus states that credit card companies focus on what consumers care about most. It is reasonable to assume that these companies would focus on something other than interest rates to compete for business.
C
most consumers would prefer paying interest on credit card debts over borrowing money from banks
This comparative statement is not supported because there is no mention of consumers’ willingness to borrow money from banks.
D
most consumers would ignore the length of time a credit card company allows to pay the balance due before interest accrues
This anti-supported. The stimulus says that most consumers intend to pay off their balance before interest accrues. There is no evidence that consumers ignore the length of time banks set before interest accrues.
E
the most intense competition among credit card companies would be over the number of places that they can get to accept their credit card
There is no mention of banks caring about the number of places they can get to accept their card. Even if you make that assumption, there is no support that this would elicit the “most intense” competition.
Summarize Argument
The author concludes that the level of carbon dioxide in the atmosphere was much higher 3 billion years ago than it is today. This is because we know that the ocean was liquid 3 billion years ago, and that required the level of greenhouses to be higher 3 billion years ago than it is today.
Notable Assumptions
The author assumes that if greenhouse gases were higher 3 billion years ago, carbon dioxide levels must have been higher 3 billion years ago. This overlooks the possibility that there were other greenhouse gases that were higher back then, while carbon dioxide levels stayed the same or were even lower.
A
Sufficient heat to keep the oceans liquid 3 billion years ago could not have been generated through geological processes such as volcanic activity.
We already know that greenhouse gases were higher 3 billion years ago, which is what helped keep the Earth warmer. The original source of the heat doesn’t change the fact that we know greenhouse gases were higher.
B
Geological studies indicate that there is much less methane in Earth’s atmosphere today than there was 3 billion years ago.
This raises the possibility that the greater levels of greenhouse gases 3 billion years ago were due to higher levels of methane. Carbon dioxide could have been equal or lower than it is today, because methane was higher.
C
Geological evidence indicates that the oceans contained greater amounts of dissolved minerals 3 billion years ago, but not enough to alter their freezing points significantly.
We already know that the ocean was liquid and that this proves greenhouse gases were higher 3 billion years ago. The freezing point of water doesn’t change how we interpret these facts.
D
The increase in the Sun’s luminosity over the past 3 billion years roughly coincided with an increasing complexity of life forms on Earth.
How the sun’s brightness correlates with the complexity of life is irrelevant. The argument concerns levels of greenhouse gases and whether higher levels of greenhouse gases imply higher levels of carbon dioxide.
E
Because the distance from Earth to the Sun has not changed significantly over the last 3 billion years, the increase in the Sun’s luminosity has resulted in more radiation reaching Earth.
We already know the Earth was liquid and that this proves greenhouse gases were higher 3 billion years ago. Levels of radiation don’t change these facts or how we interpret them. The argument concerns whether higher levels of greenhouse gases imply higher carbon dioxide levels.
Summary
The author concludes that the auto repair industry does not constitute a properly functioning free market. This is based on the following statement, which describes a requirement for being a properly functioning free market:
In order for a free market to function properly, each potential buyer of an item must be able to contact a large number of independent sellers, and compare the prices those sellers charge for the item to what the item is worth.
In order for a free market to function properly, each potential buyer of an item must be able to contact a large number of independent sellers, and compare the prices those sellers charge for the item to what the item is worth.
Missing Connection
The premise establishes a requirement for being a properly functioning free market. So if the author concludes that a certain market is not a properly functioning free market, we know the author is trying to trigger the contrapositive of the premise. In other words, the author’s assuming that market doesn’t meet the requirement. That’s how we can tell we’re looking for an answer that establishes the auto repair industry is not one in which each potential buyer can contact a larger number of independent sellers and compare the prices charged to what the item is worth.
A
People do not usually shop for auto repairs but instead take their autos to their regular repair shop out of habit.
Although (A) establishes that people usually don’t actually compare prices, this doesn’t establish that people don’t have the ABILITY to compare prices charged to what the repairs are worth. They might be ABLE to, even if they tend not to.
B
Some persons who are shopping for auto repairs cannot determine what these repairs are worth.
(B) establishes that the auto repair industry does not meet what’s required to be a properly functioning free market. If some people can’t determine what the repairs are worth, then they can’t compare prices to what the repairs are worth. So it’s not true that “each” potential buyer can compare prices to what the repairs are worth.
C
Not all auto repair shops give customers written estimates.
(C) establishes that some auto repair shops don’t give written estimates. This doesn’t establish that buyers can’t compare the prices charged to what the repairs are worth. Maybe people get verbal price estimates in person or over the phone. Or maybe they can still get price estimates from a large number of sellers, even if it’s not all sellers.
D
Many auto repair shops charge more for auto repairs than these repairs are worth.
We care about whether people can compare prices charged to what the repairs are worth. Whether the prices are higher or lower than the repairs’ worth is a separate, irrelevant issue.
E
Because it is not regulated, the auto repair industry does not have standardized prices.
(E) doesn’t establish that people can’t compare prices charged to what the repairs are worth. Even if repairs don’t have a standardized price, the repairs can still have a worth to the potential buyer. The potential buyer can still compare prices charged to that worth.
An additional note to (B).
So what we see here is quite common with correct SA answer choices. Given that the bar for correct answer in SA is sufficient, the LSAT writers have room to maneuver. They can give us something that's sufficient for the SA. In other words, they can give us a subset of what we anticipate. Allow me to illustrate.
Let's say that "all mammals are lovely therefore, Skittles is lovely." That's a crap argument but nevermind that. What's the missing SA? Simple... right... ?
Right?
Skittles is a mammal. That's what we need.
We scan the answers and don't see any answer that says Skittles is a mammal. Okay.
But (B) says Skittles is a cat. Well, don't we know that cats --> mammals? (You should.)
So choose (B) because it's a subset of what we need. In other words, (B) is sufficient for our anticipated SA answer choice. In other words, cats sufficient mammal. Cats are subsets of mammals. Subsets are sufficient for supersets.
See, one fairly common way to hide a SA answer choice is to give us an answer choice that's sufficient for the SA answer choice.
We anticipated looking for "buyers CANNOT compare prices charged for the item to see what the item is worth." (B) gave us "cannot determine worth". (B) implies what we anticipated. If it's true that we cannot determine worth, then of course it's true that we cannot compare prices to determine worth. That's like say that you cannot get to Canada implies that you cannot drive to Canada.
"Surprising" Phenomenon
Why do people invest in technologies that promise to extend life and decrease pain when those technologies are risky investments?
Objective
A hypothesis explaining this behavior will state a benefit to investors that makes the risk worthwhile. It must apply to a group of investments including those that promise to extend life and decrease pain.
A
When investments in new technologies that promise to extend life and decrease pain do provide financial return, they generally return many times the original investment, which is much more than the return on safer investments.
This explains why some investors take the risk. When such a technology does succeed, it brings a large financial benefit that makes the risk worthwhile.
B
A large variety of new technologies that promise to extend life and decrease pain have been developed in the last decade.
This does not explain why people invest in those technologies. It states that such technologies are numerous, not that they are generally successful.
C
The development of certain new technologies other than those that promise to extend life and decrease pain is also very risky, because these technologies require large amounts of capital but are unlikely to provide any financial return.
This does not state that most investments are risky, but rather identifies a new category of risky investments. Simply the existence of this category does not explain why the technologies in question attract investments.
D
Some investments that initially seem likely to provide reasonably large financial return ultimately provide no financial return.
It is not stated whether the technologies in question fit this description. It is possible that no technologies that promise to extend life and decrease pain seem likely to provide a large financial return.
E
The scientific research necessary to develop new technologies that promise to extend life and decrease pain sometimes leads to no greater understanding of the natural world.
This is irrelevant information. No relationship between the understanding of the natural world gained from research and the tendency of people to invest in that research is implied.
Summarize Argument
The department chair claims that the psychology textbook was chosen for purely academic reasons despite the associated donation. Her evidence is that the department’s textbook committee gave the textbook the highest-possible rating.
Notable Assumptions
The department chair assumes that the department’s textbook committee wasn’t affected by the donation. Thus, any connection between the donation and the committee would compromise her claim. She also assumes that either no other relevant textbook also received the highest rating, or else she would have to explain why this particular textbook was chosen for “purely academic reasons” over another textbook of comparable merit.
A
The members of the textbook committee were favorably influenced toward the textbook by the prospect of their department receiving a large donation.
The textbook committee were influenced by the donation. Thus, the fact the textbook received a high rating doesn’t signal “purely academic reasons.”
B
The department has a long-standing policy of using only textbooks that receive the committee’s highest rating.
We don’t care about tradition. We care about how the donation influenced the decision to use the textbook.
C
In the previous year, a different textbook from the same company was used in the introductory course.
We don’t care about previous years. We care about how the donation influenced the decision to use the textbook.
D
The department chair is one of the members of the textbook committee.
Even if this was true, she may have been able to give an unbiased opinion of the textbook as a committee member. And if she didn’t, the other members might’ve outvoted her.
E
The textbook company does not routinely make donations to academic departments that use its books.
They made a donation in this case.
Summary
Hemoglobin transports oxygen from the lungs throughout the body. As it picks up more oxygen molecules, a hemoglobin molecule becomes more effective at picking up additional oxygen molecules until it reaches its capacity of four. Grabbing an oxygen molecule changes the shape of the hemoglobin molecule, making it easier to receive more oxygen.
Strongly Supported Conclusions
A hemoglobin molecule with more oxygen is more effective at picking up oxygen molecules than a hemoglobin molecule with fewer oxygen molecules.
A
A hemoglobin molecule that has picked up three oxygen molecules will probably acquire a fourth oxygen molecule.
This is too strong to support. The stimulus says that it becomes increasingly likely to pick up an additional oxygen molecule but does not state that it is *likely*.
B
The only factor determining how effective a hemoglobin molecule is at picking up oxygen molecules is how open the shape of that hemoglobin molecule is.
This is too strong to support. The stimulus says that the shape of a hemoglobin molecule plays *a* factor, not that it is the sole factor.
C
A hemoglobin molecule that has picked up three oxygen molecules will be more effective at picking up another oxygen molecule than will a hemoglobin molecule that has picked up only one oxygen molecule.
This comparative statement is supported because the stimulus says that a hemoglobin molecule becomes increasingly effective at picking up more oxygen molecules the more molecules it already has.
D
A hemoglobin molecule that has picked up four oxygen molecules will have the same shape as a hemoglobin molecule that has not picked up any oxygen molecules.
There is no information about the kind of shape a hemoglobin molecule has.
E
Each hemoglobin molecule in human blood picks up between one and four oxygen molecules in or near the lungs and transports them to some other part of the body.
It is possible that a hemoglobin molecule does not pick up any oxygen molecules. No information specifies that a hemoglobin molecule has to pick up between one and four oxygen molecules.
"Surprising" Phenomenon
Why are drivers with passengers more likely to get in accidents on short trips but less likely to get in accidents on long trips?
Objective
Any hypothesis explaining this phenomenon must state some difference between short and long trips. This difference must include a distinction between solo drivers and drivers with passengers that explains why carrying a passenger increases accident risk on long trips but decreases it on short trips.
A
People are much more likely to drive alone on short trips than on long trips.
This would explain a discrepancy between the total number of accidents in each category, but not different likelihoods of getting in an accident.
B
Good drivers tend to take more long trips than bad drivers.
This does not account for a passenger changing the probability of getting in an accident. It explains a phenomenon different from the one described.
C
The longer a car trip is, the more likely a passenger is to help the driver maintain alertness.
This explains why having a passenger lowers the probability of an accident during a long trip but increases it during a short trip. Passengers on short trips distract the driver, while passengers on long trips keep the driver alert.
D
On a long trip the likelihood of an accident does not increase with each additional passenger.
This states no difference between cars with passengers and cars with no passengers. For the sake of the discrepancy, cars with multiple passengers fall into the same category as cars with one passenger.
E
Most drivers take far more short trips than long trips.
This would explain a higher number of accidents on short trips, but not the phenomenon described. It does not explain why a passenger raises the accident probability in some cases but lowers it in others.
Mayor: Clearly my opponent does not dispute the employment statistics. The unemployed voters in this city want jobs. The 8 percent increase in the number of jobs during my term exceeds that of any of my predecessors.
Summarize Argument: Counter-Position
The mayor counters the challenger’s position and implicitly concludes that she has vindicated her voters by fulfilling her promise to increase job availability. She notes that unemployed voters want jobs and that the 8% increase in the number of jobs during her term is higher than any of her predecessors.
Identify and Describe Flaw
The mayor ignores the challenger’s primary argument, which is that the 8% job increase came from a government office moving to the city with its entire staff. Because she fails to address this, the mayor doesn’t effectively counter the challenger’s argument.
A
takes for granted that those who supported the mayor in the last election believed job availability to be a significant city issue
The mayor does argue that job availability was important to her voters by saying, “The unemployed voters in this city want jobs.” But (A) doesn't describe a flaw in her argument.
B
does not consider whether the number of unemployed persons within the city represents more than 8 percent of the eligible voters
The mayor doesn’t address this, but it doesn’t describe a flaw in her argument. Even if unemployed people represent more than 8% of voters, it doesn’t change the fact that there was an 8% increase in the number of jobs during her term.
C
fails to address the challenger’s objection that the 8 percent increase did not result in an increase in job availability for those who lived in the city at the time of the last election
The mayor fails to address the objection that the 8% job increase came from a government office moving to the city with its entire staff, rather than from increased job availability for her unemployed voters.
D
ignores the challenger’s contention that the influx of newcomers during the mayor’s administration has increased the size of the voting public and altered its priorities
The challenger doesn’t make this contention. He never argues that the newcomers increased the size of the voting public and altered its priorities, so the mayor doesn't need to address this point.
E
explicitly attributes to the challenger beliefs that the challenger has neither asserted nor implied
The mayor only claims that the challenger agrees with the employment statistics. Since the challenger does cite these statistics, she isn’t falsely attributing a belief to him.