GMAT Verbal : Critical Reasoning
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Example Questions
Example Question #1 :Identifying Flaws Of Sampling
Many of the yachts anchored in Miami boast a luxurious hot tub on the top deck. Almost 80% of the yachts that were sold in the past fifteen years in Miami are older models, and none of them had built-in hot tubs.
The information above most strongly supports which of the following?
Some newer yacht models were sold in the past fifteen years in Miami.
All yachts in Miami without hot tubs were sold in the past fifteen years.
People shopping for yachts will likely choose an older-model with a hot tub than an older-model without a hot tub.
Only new yacht models come with hot tubs.
None of the newer yacht models with hot tubs will be sold in the next fifteen years.
Some newer yacht models were sold in the past fifteen years in Miami.
我们提供的两种以上的证据not allow us to make a strong enough conclusion to connect yachts to hot tubs. The first sentence tells us that an unspecified “many” of the yachts in Miami have a hot tub, but we do not know how many of these yachts are older models and how many are newer models. The second sentence tells us that
Example Question #1 :Critical Reasoning
Everyone who thinks the Rams would win the championship thought that Jones would receive the award for Most Valuable Player. But Jones did not receive the award for Most Valuable Player. Therefore, anyone who believes the Rams will win the championship is wrong.
Which one of the following arguments contains flawed reasoning most similar to that in the argument above?
Anyone who believes animals deserve better treatment believes that animals are capable of moral judgment. You do not believe that animals deserve better treatment so you do not think they are capable of moral judgment.
If you believe in fairies then you do not believe in vampires. Since Cindy believes in vampires, she cannot believe in fairies.
那些认为鸡是丑陋的认为鸭子re ugly. Since there is no reason to think ducks are ugly there is no reason to think chickens are ugly.
Anyone who thinks that eating before exercising is a good idea has never taken a health class. But Jim has never taken a health class and knows that he should not eat before exercising. Therefore, taking a health class is not necessary for you to know eating before exercising is not a good idea.
Anyone that believes that seagulls migrate based on advanced spatial recognition patterns believes that most bird species have highly developed frontal cortexes. But is has been conclusively proven that most bird species do not have highly developed frontal cortexes. Thus, the belief that seagulls migrated based on advanced spatial recognition patterns is false.
Anyone that believes that seagulls migrate based on advanced spatial recognition patterns believes that most bird species have highly developed frontal cortexes. But is has been conclusively proven that most bird species do not have highly developed frontal cortexes. Thus, the belief that seagulls migrated based on advanced spatial recognition patterns is false.
The correct answer parallels the flawed reasoning of the stimulus. Both give a situation where the first argument is dismissed on the basis that the second argument presented is false.
Example Question #1 :Parallel Reasoning
All English Springer Spaniels have long hair. All Rottweilers have short hair. Each of Tina's dogs is a cross between an English Springer Spaniel and a Rottweiler. Therefore, Tina's dogs have medium-length hair.
Which one of the following uses flawed reasoning that most closely resembles the flawed reasoning used in the argument above?
All typists who practice at least one hour per day can type one hundred words per minute. But some typists who do not practice can also type one hundred words per minute. Mike, a typist, practices thirty minutes per day. Therefore, Mike types fifty words per minute.
All players on the Wildcats have brown hair. All players on the Razorbacks have red hair. Members of the Moye family are on both the Wildcats and the Razorbacks. Therefore, some members of the Moye family have brown hair and others have red hair.
All economists know linear algebra. All physicists know relativistic mechanics. Wilma is both an economist and a physicist. Therefore, Wilma knows both linear algebra and relativistic mechanics.
All halogen gases are toxic to humans. All non-radioactive noble gases are non-toxic to humans. "Nobagen" gas is a mixture of a halogen gas and a noble gas. Therefore, "nobagen" gas is moderately toxic to humans.
All cars made by Chord are very well made. All cars made by Fysler are very poorly made. Half of the cars on Jim's lot are very well made and the other half are very poorly made. Therefore, half of the cars on Jim's lot are Chords and half are Fyslers.
All halogen gases are toxic to humans. All non-radioactive noble gases are non-toxic to humans. "Nobagen" gas is a mixture of a halogen gas and a noble gas. Therefore, "nobagen" gas is moderately toxic to humans.
The flawed reasoning used in the passage is that a combination of two "parent" items with different attributes necessarily yields a "child" product having attributes that are averages of its parents' attributes. The correct answer uses parallel reasoning inasmuch as the argument uses the fact that halogen and noble gases differ with respect to toxicity to conclude that a combination of such gases would yield a gas having toxicity that is the average of the toxicity of its "parent" gases.
Example Question #11 :Determining Which Answer Most Helps To Resolve The Paradox
After replacing her old air conditioner with a new, energy-efficient unit, Paula’s electric bills increased.
Each of the following, if true, contributes to an explanation of the increase mentioned above EXCEPT:
The new air conditioner uses a smaller share of the electricity used by Paula’s home than did the old unit.
Soon after the new air conditioner was installed, Paula adopted a child, doubling the size of her household.
Paula installed an electricity-intensive indoor tanning bed after she replaced her air conitioning unit.
Paula's electricity costs increased by 15 cents per kilowatt hour after she replaced her air conditioner.
Following the installation of her new air conditioner, Paula's neighborhood experienced a prolonged and severe heat wave, requiring heavy use of the new unit.
The new air conditioner uses a smaller share of the electricity used by Paula’s home than did the old unit.
The correct answer here is the one that doesnotexplain the apparent paradox. That the new unit uses a smaller share of total electricity is consistent with its being more energy efficient. It does not explain how her electric bills could have gone up despite her installation of the more efficient unit; all other answers provide possible resolutions of such apparent paradox.
Example Question #2 :Critical Reasoning
Advertisement: Coma Cola is the best-tasting cola on the market and we conducted a test using over 1000 cola consumers to prove it. Each consumer was given two identical cups filled with a carbonated beverage from the same fountain. One cup was filled with Coma Cola and the other was filled with unadulterated soda water. Ninety-nine percent of the consumers preferred the Coma Cola. So, Coma Cola is the best tasting cola available.
The advertisement’s reasoning is most vulnerable to criticism on the grounds that it fails to consider whether ___________________
The consumers tested had the opportunity to evaluate colas other than Coma Cola.
Any portion of the population is allergic to any of the ingredients in Coma Cola.
The consumers tested had the opportunity to evaluate flavored soft drinks other than colas.
Coma Cola has more or less caffeine than other colas.
昏迷可乐或更便宜expensive than other colas.
The consumers tested had the opportunity to evaluate colas other than Coma Cola.
The advertisement's claim, that Coma Cola is the best tasting cola, is based on 99% percent of cola consumers choosing it over soda water. The flaw in the experimental setup is that just because a consumer chooses Coma Cola over soda water, it does not mean that she will choose Coma Cola over any other cola, let alone over all other colas.
The correct answer recognizes that, in order to validly make such a claim, one would have to show a preference for Coma Cola over other colas, not over soda water (or even over other flavored soft drinks, as one of the incorrect answer choices indicates).
Example Question #52 :Gmat口头
Eggplants are always purple. John bought a purple vegetable. Therefore, it was an eggplant.
Which of the following arguments contains reasoning most similar to the flawed reasoning in the above argument?
除了2,质数总是很奇怪。怒江mber 13 is odd. Therefore, it is prime.
Jenny always eats healthy. Salmon is a healthy food. Therefore, she eats salmon.
蓝知更鸟并不总是蓝色的。一个棕色的鸟你tside the window. Therefore, it may or may not have been a blue bird.
Rabbits are fast creatures. A fast creature ran by. Therefore, it may have been a rabbit.
Gambling is a risky hobby. Jamie likes taking risks. Therefore, she likes to gamble.
除了2,质数总是很奇怪。怒江mber 13 is odd. Therefore, it is prime.
In this argument, the flaw is framed in the following way:
X is always Y. A is Y. Therefore, A is X.
(Just because X is always Y does NOT mean that Y is always X.)
The flawed argument is therefore most like:
除了2,质数总是很奇怪。怒江mber 13 is odd. Therefore, it is prime.
Here
x= prime numbers
Y = odd
A = 13
The structure of this argument is the same as the structure argument in:
Eggplants are always purple. John bought a purple vegetable. Therefore, it was an eggplant.
X= eggplants
Y = purple
A = purple vegetable
Example Question #1 :Identifying Causal Flaws
Two students were given practice exams. One exam ordered the questions from hardest to easiest, while the other exam ordered the questions from easiest to hardest. The student who took the test with questions ordered hardest to easiest performed more poorly than the other student. Therefore, tests that ordered hardest to easiest will cause a student to perform more poorly.
This argument is most vulnerable to criticism if which of the following statements is true?
The students had the same grade point averages.
The student who performed more poorly has a lower grade point average than the other student.
The students took the exam in different classrooms, one of which was more spacious.
The test consisted solely of math questions, rather than being a blend of content.
One student was from Los Angeles, while the other student was from New York.
The student who performed more poorly has a lower grade point average than the other student.
The conclusion of this argument is that when questions are ordered hardest to easiest, students perform more poorly on them. In order to refute this causal assertion, another source of the poor performance must be introduced. The fact that the student who performed more poorly has a lower grade point average than the other student is a significant intervening cause, and therefore the correct answer.
Example Question #1 :Critical Reasoning
Thousands of people contract tonsillitis every year, and yet all go on to live normal lives after the operation. We can conclude, from this observation, that the tonsils have no function in the body.
The argument would be most weakened by which of the following, if it were true?
People live normal lives after appendectomies, but the appendix is known to be part of the digestive system.
The tonsils have been shown to have a vital role to play in the physiology of laboratory rabbits and mice.
The human tonsil develops as part of the immune system, a system of vital importance in defense against disease.
Another part of the body can take over the function of the tonsils if they are removed.
Tonsillectomies are performed only when the tonsils become seriously infected.
Another part of the body can take over the function of the tonsils if they are removed.
The conclusion states that the tonsils have no function in the body. To weaken this conclusion, we should try to show that the tonsils do in fact have a function, at least at some point in human life. Comparison with another organ is not really useful, as they might be very different from tonsils, and what happens in other animals is also not directly relevant. And discussing where the tonsils develop has nothing to do with their function. Finally, though an organ might develop as part of a system and yet have no function (like the appendix or muscles that wiggle the ear), the only answer left suggests there is a function even though this function can be taken over by another part of the body. This suggestion most weakens the argument posed above.
Example Question #1 :Critical Reasoning
According to an article in a nutritional magazine, eating beets significantly lowers the risk of cancer. The article refers to a study that found that people who consumed one or more beets per day were half as likely to be diagnosed with cancer as people who did not.
Which of the following, if true, most weakens the argument in the magazine article?
Another study found that people who consumed one tablespoon of fish oil per day were more than four times less likely to be diagnosed with cancer as those who did not.
The study was only conducted in one city.
Participants in the study reported consuming no vegetables other than beets.
In another experiment, cancer patients who ate one or more beets per day were no more likely to recover than those who ate no beets.
The participants in the study who ate beets were more likely to exercise regularly than those who did not eat beets.
The participants in the study who ate beets were more likely to exercise regularly than those who did not eat beets.
Because study participants who ate beets were also more likely to exercise regularly than those who did not eat beets, it is impossible to determine whether beets or regular exercise were more influential in preventing cancer. Thus this is the correct answer.
Example Question #1 :Identifying Causal Flaws
Students from outside the province of Merryweather, who in any given academic year pay twice as much tuition each as do students from within Merryweather, had traditionally accounted for at least two-thirds of the enrollment at Central Merryweather College. Over the past
下列哪一个reasonably be inferred from the statements above?
If the college’s per capita revenue from tuition has remained the same, tuition fees have increased over the past
Over the past
If academic standards had not risen over the past
If it had not been for the high tuition paid by students from outside Merryweather, the college could not have improved its academic standards over the past
Over the past
If the college’s per capita revenue from tuition has remained the same, tuition fees have increased over the past
Since we cannot say what was responsible for the increased academic standards, we can rule out any attempt to explain it. It could be that more residents of Merryweather began to attend the school, as opposed to a reduction in those from outside Merryweather, or vice versa, so avoid explanations as to why the population decreased.
The only thing we can infer from the information given is that there could be tuition increases if per capita revenue remained the same: Say students not from Merryweather used to account for
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