Interior decorator: All coffeehouses and restaurants are public places. Most well-designed public places feature artwork. But if a public place is uncomfortable it is not well designed, and all comfortable public places have spacious interiors.
Summary
All coffeehouses are public places.
All restaurants are public places.
Most well-designed public places feature artwork.
If a public place is uncomfortable it is not well-designed.
All comfortable public places have spacious interiors.
Notable Valid Inferences
We can connect the conditional statements in the last sentence. If a public place is well-designed, that means it is comfortable. That in turn means the well-designed public place has a spacious interior.
A
Any restaurant that has a spacious interior is comfortable.
Could be false. We know all public places that are comfortable have spacious interiors. That doesn’t imply all public places with spacious interiors are comfortable. They might be uncomfortable places despite having spacious interiors.
B
Most public places that feature artwork are well designed.
Could be false. We know most well-designed public places feature artwork. That doesn’t mean most public places featuring artwork are well-designed. Most A is B doesn’t imply Most B is A.
C
Most coffeehouses that are well designed feature artwork.
Could be false. We know most well-designed public places feature artwork. Coffeehouses are just one kind of public place. The well-designed public places that feature artwork might just be other kinds of public places besides coffeehouses.
D
Any well-designed coffeehouse or restaurant has a spacious interior.
Must be true. Coffeehouses and restaurants are public places. So, if they’re well-designed, they must be comfortable. If they’re comfortable, they have a spacious interior.
E
Any coffeehouse that has a spacious interior is a well-designed public place.
Could be false. We know well-designed public places have spacious interiors. That doesn’t imply all public places with spacious interiors are well-designed. There could be some public places with spacious interiors that are not well-designed.
"Surprising" Phenomenon
In forests that get a lot of acid rain, why are sugar maples more likely to show signs of decline consistent with calcium deficiency than are spruces or firs, even though all three kind of trees need calcium to survive and acid rain tends to lead to lower calcium levels in soil?
Objective
The correct answer will tell us about a difference between sugar maples and the other two kinds of trees that could lead to sugar maples being more likely to suffer from effects of calcium deficiency than are the other kinds of trees.
A
Soil in which calcium levels are significantly diminished by acid rain is also likely to be damaged in other ways by acid rain.
This doesn’t differentiate sugar maples from spruces and firs.
B
Sugar maples that do not receive enough calcium deteriorate less rapidly than spruces or firs that do not receive enough calcium.
This makes the discrepancy more difficult to explain, because it suggests sugar maples would be healthier than spruces and firs when they don’t get enough calcium. But sugar maples actually show more signs of decline.
C
Spruces and firs, unlike sugar maples, can extract calcium from a mineral compound that is common in soil and is not affected by acid rain.
This explains how spruces and firs can get more calcium than sugar maples, even when acid rain lowers levels of calcium in the soil. A non-soil source of calcium could lead to spruces and firs being less likely to suffer from calcium decline.
D
Sugar maples require more calcium in the spring and summer than they do in the fall and winter.
This doesn’t differentiate sugar maples from spruces and firs. We have no reason to think spruces and firs don’t have the same feature that this answer describes. So, we’re still left wondering why sugar maples are more likely to show signs of decline than the other trees.
E
Unlike spruces or firs, most sugar maples are native to areas that receive a lot of acid rain.
The stimulus compares sugar maples in forests that get a lot of acid rain with spruces and firs “in such forests.” So, we’re just talking about spruces and firs in forests that do get lots of acid rain.
Summarize Argument
The travel industry consultant concludes that these airlines are too concerned about the comfort of business class travelers and should instead prioritize the comfort of leisure travelers. He bases this on the fact that 80% of all airline tickets are purchased by leisure travelers.
Notable Assumptions
The travel industry consultant assumes that the comfort of leisure travelers is more important than the comfort of business class travelers, simply because leisure travelers purchase more tickets.
He also assumes that, just because leisure travelers purchase 80% of airline tickets overall, they also purchase 80% of tickets on each airline. It’s possible that the airlines that conducted these surveys are luxury airlines with far fewer leisure travelers than most airlines have.
He also assumes that, just because leisure travelers purchase 80% of airline tickets overall, they also purchase 80% of tickets on each airline. It’s possible that the airlines that conducted these surveys are luxury airlines with far fewer leisure travelers than most airlines have.
A
Business travelers often make travel decisions based on whether they feel a given airline values their business.
This may explain why airlines are working to improve business travelers’ comfort, but it doesn’t weaken the conclusion that airlines should instead focus on leisure travelers. We can’t assume that focusing on leisure travelers would make business travelers feel less valued.
B
Some airlines have indicated that they will undertake alterations in seating space throughout the entire passenger area of their planes in the near future.
We don't know what "alterations" means here. It could mean reducing space for leisure travelers to increase it for business travelers. Either way, (B) doesn't weaken the conclusion that airlines should prioritize leisure travelers over business travelers.
C
Sleeping in comfort during long flights is not the primary concern of leisure travelers.
It doesn’t matter what the primary concern of leisure travelers is. We need an answer choice that shows that just because they purchase 80% of all airline tickets doesn’t mean that leisure travelers’ comfort is more important than other passengers’ comfort.
D
A far greater proportion of an airline’s revenues is derived from business travelers than from leisure travelers.
(D) weakens the argument by implying that the assumption that leisure travelers’ comfort is more important because they purchase 80% of airline tickets is false. Just because they purchase more tickets, doesn’t mean that leisure travelers contribute more to airlines’ revenues.
E
Most leisure travelers buy airline tickets only when fares are discounted.
This doesn’t weaken the author’s conclusion because we don’t know how much these discounted fares affect airlines’ profits. The assumption remains that, just because leisure travelers purchase 80% of tickets, their comfort should be prioritized.
Logan: I disagree. Schoolchildren should acquire the fundamental knowledge necessary for future success, and they learn such fundamentals only through disciplined, systematic instruction from accredited teachers.
Speaker 1 Summary
Gaby says that children in school should get to follow their interests, with support from teachers but minimal guidance. In support, Gaby claims that this model of education would enable the children to be most successful as adults.
Speaker 2 Summary
Logan argues that Gaby is wrong; in other words, children should not just follow their interests in school. Why not? Because children should learn fundamental knowledge that they need to succeed in the future. Logan says that this is only possible through disciplined and systematic teaching, which is at odds with freely following various interests.
Objective
We’re looking for a point of disagreement. Gaby and Logan disagree about the best model of education: free exploration or disciplined and systematic instruction.
A
the way in which schoolchildren best acquire fundamental knowledge
Logan thinks that the only way for children to acquire fundamental knowledge is through disciplined and systematic instruction, but Gaby doesn’t disagree. In fact, Gaby doesn’t talk about fundamental knowledge at all.
B
the extent to which teachers should direct schoolchildren’s education
Gaby thinks that teachers should minimally direct education, but Logan thinks they should provide a lot of direction: this is the point of disagreement. Logan doesn’t say this outright, but “disciplined, systematic instruction” indicates a teacher-directed structure.
C
the importance of having qualified teachers involved in schoolchildren’s education
Both speakers indicate that it’s important for qualified teachers to be involved in education. Gaby talks about “experienced” teachers and Logan talks about “accredited” teachers, meaning both of them care about teachers’ qualifications.
D
the sort of school environment that most fosters children’s creativity
Neither speaker talks about creativity. Gaby’s proposal sounds like it might foster creativity, but that’s not a claim Gaby actually makes, just that it will enable success. Likewise, Logan talks about “fundamentals” without mentioning if creativity is included.
E
the extent to which schoolchildren are interested in fundamental academic subjects
Neither speaker talks about whether children are interested in fundamental academic subjects. Gaby talks about letting children follow their interest, and Logan talks about fundamental knowledge, but neither mentions if there’s an overlap between the two.
Summary
Nutrient-rich sewage can pollute and overnutrify estuary waters.
Overnutrified estuary waters cause algae to proliferate.
Abundant algae can be a food source for microorganisms that are toxic to fish.
These microorganisms kill most fish in the estuary.
Overnutrified estuary waters cause algae to proliferate.
Abundant algae can be a food source for microorganisms that are toxic to fish.
These microorganisms kill most fish in the estuary.
Very Strongly Supported Conclusions
Abundant algae in an estuary can cause most fish in the estuary to die.
Overnutrified estuary waters can cause most fish in the estuary to die.
Nutrient-rich sewage pollution can cause most fish in an estuary to die.
Overnutrified estuary waters can cause most fish in the estuary to die.
Nutrient-rich sewage pollution can cause most fish in an estuary to die.
A
Fish in an estuary that has been polluted by sewage are generally more likely to die from pollution than are fish in an estuary that has been polluted in some other way.
Unsupported. Nutrient-rich sewage can kill most fish in an estuary, but we don’t know that it’s more likely to than other forms of pollution.
B
In estuary waters that contain abundant algae, microorganisms that are toxic to fish reproduce more quickly than other types of microorganisms.
Unsupported. Abundant algae can be a food source for toxic microorganisms, but we don’t know that it causes toxic microorganisms to reproduce more quickly than other types of microorganisms.
C
Nutrients and other components of sewage do not harm fish in coastal estuaries in any way other than through the resulting proliferation of toxic microorganisms.
Unsupported. Nutrient-rich sewage can harm fish in estuaries by causing algae to grow, which feeds toxic microorganisms. But it might harm fish in other ways too.
D
Algae will not proliferate in coastal estuaries that are not polluted by nutrient-rich sewage.
Unsupported. Overnutrified waters do cause algae to proliferate, but it might proliferate in other conditions too.
E
Overnutrifying estuary waters by sewage can result in the death of most of the fish in the estuary.
Very strongly supported. Overnutrified estuary waters cause algae to proliferate, which can then feed toxic microorganisms that kill most fish in the estuary. So, nutrient-rich sewage pollution can cause the death of most fish in an estuary.
Summarize Argument
Archaeologists hypothesize that ancient andacite stones were brought to Tiwanaku on reed boats. As evidence, they point to an experiment where a 9-ton stone was transported from Copacabana to Tiwanaku using a reed boat built with traditional techniques and materials.
Notable Assumptions
The archaeologists assume that the same reed boats that transported a 9-ton stone could’ve also transported a 40-ton stone. The archaeologists also assume that the traditional techniques in question were being used at the time these stones were quarried and transported to Tiwanaku.
A
whether the traditional techniques for building reed boats were in use at the time Tiwanaku was inhabited
If the answer here is yes, then the archaeologists’ argument seems to work: traditional techniques were capable of transporting the stones. If the answer is no, then the archaeologists would need different evidence to show the inhabitants could’ve transported the stones.
B
whether green andacite stones quarried at the time Tiwanaku was inhabited were used at any sites near Copacabana
We don’t care if they were used at nearby sites. Even if they were, they still could’ve been used at Tiwanaku.
C
whether reed boats are commonly used today on the lake
We don’t care about reed boats today. We care about read boats back when the andacite stones were quarried and transported to Tiwanaku.
D
whether the green andacite stones at Tiwanaku are the largest stones at the site
There could be heavier stones that simply weren’t quarried at Copacabana. We don’t care about stones that weren’t quarried at Copacabana.
E
whether the reed boat built for the experimenters is durable enough to remain usable for several years
The inhabitants could’ve kept building new reed boats. We have no reason to think those boats would have to last for several years for the archaeologists’ argument to work.
Summarize Argument
The author concludes that we shouldn’t strike now. This is based on the fact that a strike would cause the union to suffer a major financial loss.
Identify and Describe Flaw
The author overlooks the possibility that the benefits of striking would outweigh the impact of the major financial loss.
A
fails to consider that a strike might cause the union to suffer a financial loss even if no fine were imposed
The premise establishes that there would be a major financial loss because of a fine. Whether there would be a financial loss for another reason if the fine were not imposed doesn’t change the fact that there would still be financial loss.
B
fails to define adequately what constitutes a major financial loss
The argument doesn’t need to define what constitutes a major financial loss. The premise establishes there will be a major financial loss; exactly how much money is lost doesn’t affect the reasoning.
C
fails to consider that the benefits to be gained from a strike might outweigh the costs
The author overlooks the possibility that the benefits of striking might outweigh the negative impact of a major financial loss. So striking might be worth doing now, despite that loss.
D
takes for granted that the most important factor in the labor union’s bargaining position is the union’s financial strength
The author doesn’t assume that financial strength is the most important factor in the union’s bargaining position. Although the author does assume that a major financial loss is negative, we don’t know whether it has anything to do with bargaining position.
E
fails to establish that there will be a better opportunity to strike at a later time
The author doesn’t assume that there will be a better opportunity to strike later. The author might believe that the union shouldn’t strike later, too.