GMAT-邏輯推理題critical-reasoning(課堂)課件

1、Critical ReasoningPeter Pan1Critical ReasoningPeter Pan1A000002股票在明天還會(huì)上漲到今天為止，A000002股票出現(xiàn)三天連續(xù)上漲該股票出現(xiàn)三天連漲后，第四天也會(huì)上漲PremiseConclusion Assumption AssumptionPremiseConclusionCritical ReasoningArgument Structure 2A000002股票在明天還會(huì)上漲到今天為止，A000002股Critical ReasoningArgument Structure A000002股票在明天還會(huì)上漲到今天為止，A000

2、002股票出現(xiàn)三天連續(xù)上漲根據(jù)數(shù)據(jù)統(tǒng)計(jì)，該股票出現(xiàn)三天連漲后，第四天有80% 的情況都是上漲。這段時(shí)間該股票的運(yùn)行情況和以前第四天出現(xiàn)上漲的情況相似中國(guó)股市從來(lái)沒(méi)有規(guī)律3Critical ReasoningArgument StCritical ReasoningArgument Structure Studying regularly is one factor that has been shown to improve ones performance on the SAT. Melissa took the SAT and Scored a 1500. If she studies s

3、everal times a weak, Melissa can expect to improve her score.Melissa can expect to improve her score.Studying regularly is one factor that has been shown to improve ones performance on the SAT. Melissa took the SAT and Scored a 1500. Studying several times a weak qualifies as studying regularly4Crit

4、ical ReasoningArgument St AssumptionPremiseConclusion5 AssumptionPremiseConclusion5Critical ReasoningFind the Premisestated pieces of information or evidence that generally provide support for the given conclusioncould be Facts, opinions, claimsshowing backgroundtelling a story Several industries ha

5、ve recently switched at least partly from older technologies powered by fossil fuels to new technologies powered by electricity. It is thus evident that less fossil fuel is being used as a result of the operations of these industries than would have been used if these industries had retained their o

6、lder technologies. 6Critical ReasoningFind the PrCritical ReasoningCommon Signal WordPremiseConclusion AssumptionTherefore, As a result, Suggests, Indicates, Accordingly, So, Consequently, Thus, Hence, It follows thatSinceDue toAs a result ofBecauseGiven thatAs7Critical ReasoningPremiseConclManager:

7、 the new manufacturing process should save us time in the end,even though the first step of the five-step process will take twice as long asit does under the old process. Far fewer of the components will be founddefective and the sole purpose of steps two and three under the old processis to weed ou

8、t defective components. As a result, we should be able to eliminate two of the five steps in the existing manufacturing process.Which of the following would be most useful in evaluating the claim made inthe argument?Therefore Test(1) X, therefore Y. If this works, Y is the conclusion.(2) Y, therefor

9、e X. If this works, X is the conclusion.Critical ReasoningFind the ConclusionX: The new process should save us time.Y: we should be able to eliminate two of the five steps in the process.8Manager: the new manufacturingCritical ReasoningDraw the Conclusion緊跟前提條件Curbing government spending has been de

10、monstrated to raise the value of a countrys currency over time. However, many economists no longer recommend this policy. A currency of lesser value causes a countrys exports to be more competitive in the international market, encouraging domestic industries and making the economy more attractive to

11、 foreign investment.The statements above most strongly support which of the following inferences?(A) Limited government spending can also lead to a reduction in the national deficit.(B) Curbing government spending can make a countrys exports less competitive.(C) Many economists now recommend higher

12、levels of government spending.(D) An increase in the value of a currency will result in reduced government spending.(E)Competitive exports indicate a-weak currency.9Critical Reasoning緊跟前提條件CurbinCritical ReasoningDraw the ConclusionCurbing government spending has been demonstrated to raise the value

13、 of a countrys currency over time. However, many economists no longer recommend this policy. A currency of lesser value causes a countrys exports to be more competitive in the international market, encouraging domestic industries and making the economy more attractive to foreign investment.The state

14、ments above most strongly support which of the following inferences?(A) Limited government spending can also lead to a reduction in the national deficit.(B) Curbing government spending can make a countrys exports less competitive.(C) Many economists now recommend higher levels of government spending

15、.(D) An increase in the value of a currency will result in reduced government spending.(E)Competitive exports indicate a weak currency.F）Government investment can make a countrys exports less competitive.超出前提討論范圍超出前提討論范圍偷換概念因果倒置因果倒置10Critical ReasoningCurbing gove Increases in the level of high-dens

16、ity lipoprotein (HDL) in the human bloodstream lower bloodstream-cholesterol levels by increasing the body capacity to rid itself of excess cholesterol. Levels of HDL in the bloodstream of some individuals are significantly increased by a program of regular exercise and weight reduction. Which of th

17、e following can be correctly inferred from the statements above?Individuals who are underweight do not run any risk of developing high level of cholesterol in the bloodstream.Individuals who do not exercise regularly have a high risk of developing high level of cholesterol in the bloodstream late in

18、 life.Exercise and weight reduction are the most effective methods of lowering bloodstream cholesterol levels in humans.A program of regular exercise and weight reduction lowers cholesterol levels in the bloodstream of some individuals.Only regular exercise is necessary to decrease cholesterol level

19、s in the bloodstream of individuals of average weight.Critical ReasoningDraw the Conclusion11 Increases in the level of higThe average fuel efficiency of vehicles sold nationwide during the period 2000-2004 was 25 miles per gallon; the corresponding figure during the period 1995-1999 was 20 miles pe

20、r gallon. The national average price of gasoline during the period 2000-2004 was $2 per gallon; the corresponding figure during the period 1995-1999 was $1.60 per gallon.The statements above, if true, best support which of the following conclusions?(A) The average fuel efficiency of vehicles sold na

21、tionwide should reach 30 miles per gallon for the period 2005-2009.(B) The national average price of gasoline during 1997 was lower than the corresponding price during 2003.(C) Rising gasoline prices lead consumers to purchase more fuel-efficient cars.(D) Between the two described time periods, the

22、national average fuel efficiency and the national average gasoline price both increased at roughly the same rate.(E) Consumers spent more money on gasoline during the period 2060-2004 than during the period 1995-1999.Critical ReasoningDraw the Conclusion12The average fuel efficiency ofLogic fallacie

23、s1313Critical ReasoningDraw the ConclusionIn certain congested urban areas, commuters who use public transportationoptions, such as trains and subways, spend approximately 25 percent lesstime in transit, on average, to reach their destinations than commuters whotravel by car. Even individuals who dr

24、ive their entire commute in carpoollanes, which are typically the least congested sections of roadways, stillspend more time, on average, than commuters who use trains and subways.The statements above, if true, best support which of the following assertions about commuting in the congested urban are

25、as mentioned above?(A) Waiting in traffic accounts for approximately 25 percent of the commuting time for individuals who drive to their destinations.(8) Walking between a subway or train station and ones final destination does not, on average, take longer than walking between ones car and ones fina

26、l destination.(C) Using carpool lanes does not, on average, reduce driving time by morethan 25 percent.(D) Individuals who commute via public buses spend approximately 25 percent more time in transit than those who commute using public trains or subways.(E)Subways and trains are available in the maj

27、ority of congested urban areas.14Critical ReasoningIn certain cCritical ReasoningDraw the Conclusion15Critical Reasoning15Critical ReasoningFind the Assumption(A) Viewers are more interested in sports and weather than in personal interest stories.(B) The programming content of Nighttime News is more

28、 closely aligned with the interests of the overall audience than is the content of World News.(C) Some World News viewers liked the new Nighttime News programming better than they liked the World News programming.(D) There are other possible causes for an increase in the number of viewers of Nightti

29、me News, including a recent ad campaign that aired on many local affiliates.(E) The quality of World News will remain constant even if Nighttime News improves.For several years, Nighttime News attracted fewer viewers than World News,which broadcasts its show at the same time as Nighttime News . Rece

30、ntly,the producers of Nighttime News added personal interest stories andincreased coverage of sports and weather. The two programs now have aroughly equal number of viewers. Clearly, the recent programming changespersuaded viewers to switch from World News to Nighttime News.Which of the following is

31、 an assumption on which the author relies?16Critical Reasoning(A) Viewers (1) bridge a gap between any premise and the conclusion, and(2) support/ strengthen/validate the conclusion.Critical ReasoningFind the AssumptionPremiseConclusion Assumption17(1) bridge a gap between any pThe local university

32、recently hired a new soccer coach. Although she has several years worth of coaching experience and is a diligent student of the game, she was never a member of a collegiate soccer team. For this reason, the new coach will be unable to build a successful program.The argument above is based on which o

33、f the following assumptions?(A) The local university should have hired a former collegiate soccer player as its new coach.(B) Coaching experience is one of the most crucial factors for coaching success.(C) The previous coach at the university was dismissed due to her lack of success(D) To build a su

34、ccessful soccer program as a coach, one must be a former collegiate soccer player.(E) The university does not plan to provide the new coach with the resources necessary to build a successful program. Critical ReasoningFind the Assumption緊跟結(jié)論，不能轉(zhuǎn)移話(huà)題重心18The local university recently 緊跟結(jié)論When news peri

35、odicals begin forecasting a recession, people tend to spendless money on discretionary purchases. Therefore, the perceived threat ofrecession decreases the willingness of people to purchase products that theyregard as optional or luxury goods.The argument above assumes that _(A) there are more luxur

36、y goods available after a recession is forecast(B) recently, the threat of recession has been increasingly publicized as newsperiodicals have grown more pervasive(C) most people do not regularly read news periodicals(D) peoples perception of the threat of recession increases when newsperiodicals beg

37、in forecasting a recession(E) the people who spent the most money before a recession was forecastwere among those who curtailed their spending after the recession becameapparentCritical ReasoningFind the Assumption19緊跟結(jié)論When news periodicals begiCritical ReasoningFind the Assumption緊跟結(jié)論P(yáng)remiseConclu

38、sion AssumptionNews periodicals publish the forecast of a recessionPeople spend less money on discretionary itemsTherefore, the perceived threat causes people to spend less moneyAs a result, peoples perception of the threat of a recession increases As a result, peoples perception of the threat of a

39、recession does not increases Negating any correct assumption will destroy the argument 20Critical Reasoning緊跟結(jié)論P(yáng)remiseCCritical ReasoningFind the Assumption緊跟結(jié)論Sam is currently the deputy mayor of Geneva County. Therefore, Sam should be the next mayor of Geneva when the current mayor retiresWhich of

40、 the following is an assumption on which the author relies?Imagine two possible answer choices:(A) Sam is the most honest person in the whole county.(B) The deputy mayor is always the best person to become the next mayor when a current mayor retires.Sam is NOT NECESSARILY the most honest person in t

41、he whole county.The deputy mayor is NOT NECESSARILY the best person to become the next mayor when a current mayor retires.21Critical Reasoning緊跟結(jié)論Sam is cAlways. only. all: insert Not necessarily. or Some . not in place of All.(B) Tomatoes are always red.LEN: Tomatoes are NOT NECESSARILY always red.

42、Never. none, not one. not once: change to At least one or at least once.(D) Not one player was late for practice.LEN: AT LEAST ONE player was late for practice.Some, a few, several: change to No or None. (Notice that this may sound extreme)(A) Some cats purr when you pet them.LEN: NO cats purr when

43、you pet them.Sometimes, on Occasion, often: change to Never. (Notice that this may sound extreme)(A) Cats sometimes purr when you pet them.LEN: Cats NEVER purr when you pet them.At least, at most. more than, less than: change to the mathematically opposite term.(C) She has at least three different j

44、ob offers.LEN: She has LESS THAN THREE different job offers.Critical ReasoningFind the Assumption22Always. only. all: insert Not 2323Critical ReasoningFind the Assumption緊跟結(jié)論For several years, Nighttime News attracted fewer viewers than World News,which broadcasts its show at the same time as Nightt

45、ime News Recently,the producers of Nighttime News added personal interest stories andincreased coverage of sports and weather. The two programs now have aroughly equal number of viewers. Clearly, the recent programming changespersuaded viewers to switch from World News to Nighttime News.Which of the

46、 following is an assumption on which the author relies?(A) Viewers are more interested in sports and weather than in personal interest stories.(B) The programming content of Nighttime News is more closely aligned with the interests of the overall audience than is the content of World News.(C) Some W

47、orld News viewers liked the new Nighttime News programming better than they liked the World News programming.(0) There are other possible causes for an increase in the number of viewers of Nighttime News, including a recent ad campaign that aired on many local affiliates.(E) The quality of World New

48、s will remain constant even if Nighttime News improves.24Critical Reasoning緊跟結(jié)論For seveAssumptions can serve to fill in a logic gapAssumptions can establish the feasibility of the premises of the argumentAssumptions can eliminate alternate paths to reach a given conclusionCritical ReasoningFind the

49、AssumptionCategories of AssumptionSidneys get-rich-quick scheme is sure to succeed. He will buy undervalued properties in foreclosure. Then he will resell the properties to a local real estate developer and generate large profits.Undervalued properties exist in foreclosure and easily can be found an

50、d purchased by Sidney.25Assumptions can serve to fill Assumptions can serve to fill in a logic gapAssumptions can establish the feasibility of the premises of the argumentAssumptions can eliminate alternate paths to reach a given conclusionAssumptions can eliminate alternate causes for a given concl

51、usion.Critical ReasoningFind the AssumptionCategories of AssumptionA magazine published an article proclaiming that one can get a promotion by playing golf with ones boss. Kevin concludes that the best way for him to get promoted is to take golf lessons and join his bosss country club.There are no o

52、ther better ways to gain a promotion than to play golf with ones boss.26Assumptions can serve to fill Assumptions can serve to fill in a logic gapAssumptions can establish the feasibility of the premises of the argumentAssumptions can eliminate alternate paths to reach a given conclusionAssumptions

53、can eliminate alternate causes for a given conclusion.Critical ReasoningFind the AssumptionCategories of AssumptionScientists have discovered that people with Elmers disease have elevatedlevels of elastomer in their blood.The scientists concluded that a person without Elmers disease but with elevate

54、d levels of elastomer in the blood is likely to develop Elmers disease in the future.Correlation but not causationElmers disease is not the cause of the elastomer levels27Assumptions can serve to fill Economists have noticed that countries with more developed cultures ofentrepreneurship and risk-tak

55、ing have higher economic growth rates.Therefore, they have concluded that cultures of entrepreneurship and risk-taking generate higher rates of growth over time.Critical ReasoningFind the AssumptionHigher growth rates in an economy do not contribute to a more highly developed culture of entrepreneur

56、ship and risk-taking.Countries with high economic growth rates typically have low unemployment rates.Higher economic growth rates in a given country tend to result in increased levels of entrepreneurship and risk-taking.Economists found the cultures of entrepreneurship and risk-taking is the reason

57、to a higher rates of a countrys wealth growth.錯(cuò)誤答案是怎么錯(cuò)的偷換概念因果倒置超出討論范圍無(wú)關(guān)28Economists have noticed that cCritical ReasoningFind the Assumption29Critical Reasoning29Whether the expected service life of LED arrays is at least as long as that of the currently used incandescent bulbs Whether any cities ha

58、ve switched from incandescent lights in their traffic signals to lighting elements other than LED arrays Whether the company from which Traverton currently buys incandescent bulbs for traffic signals also sells LED arrays Whether Travertons city council plans to increase the number of traffic signal

59、 lights in TravertonWhether the crews that currently replace incandescent bulbs in Travertons traffic signals know how to convert the existing fixtures so as to accept LED arraysTravertons city council wants to minimize the citys average yearly expenditures on its traffic signal lights and so is con

60、sidering replacing the incandescent bulbs currently in use with arrays of light-emitting diodes (LEDs) as the incandescent bulbs burn out. Compared to incandescent bulbs, LED arrays consume significantly less energy and cost no more to purchase. Moreover, the costs associated with the conversion of