【每日逻辑练习第二季】【1-20】

fox0923

逻辑小分队迎来了第一个系列的最后一贴~~下面等待大家的就是入群选拔拉，大家等候好消息吧~~希望大家在今后的2，3，4.....系列继续跟进和我们一起练习击垮CR~~

--------------------------------狐狐分界线-----------------------------------------
结束了Weaken CR的练习，大家应该都收获了不少吧，接下来再接再厉，上我们Strengthen的题目~加油加油！！


精练


1. Advertisement: At most jewelry stores, the person
assessing the diamond is the person selling it so
you can see why an assessor might say that a
diamond is of higher quality than it really is.
But because all diamonds sold at Gem World
are certified in writing, you’re assured of a fair
price when purchasing a diamond from Gem
World.


The reasoning in the advertisement would be most
strengthened if which one of the following were true?
(A) Many jewelry stores other than Gem World also
provide written certification of the quality of
their diamonds.
(B) The certifications of diamonds at Gem World
are written by people with years of
experience in appraising gems.
(C) The diamonds sold at Gem World are generally
of higher quality than those sold at other
jewelry stores.
(D) The diamond market is so volatile that prices of
the most expensive diamonds can change by
hundreds of dollars from one day to the next.
(E) The written certifications of diamonds at Gem
World are provided by an independent
company of gem specialists.




PREP CR 2 逻辑练习


5.    (24305-!-item-!-188;#058&001204)


Microscopic plants called algae grow inside the top layer of sea ice in the Antarctic if enough sunlight reaches that layer of ice and enough seawater, which contains nutrients, reaches that layer after splashing onto the surface.  Even though moderate snow cover reduces the sunlight that filters into the top layer, sea ice with moderate snow cover typically contains even more algae in the top layer than does sea ice with less snow cover.


Which of the following, if true, most helps to explain the apparent discrepancy?


(A) As the weight of accumulated snow forces ice lower in the water, more seawater splashes onto the surface and seeps through the snow.
(B) Seawater in the Antarctic often contains higher concentrations of nutrients than does seawater in more temperate regions.
(C) As the air temperature around sea ice decreases during the winter, the likelihood decreases that snow will fall and thus add to any existing snow cover.
(D) The nutrients on which algae rely are common in seawater throughout the Antarctic.
(E) More sunlight filters through a layer of ice than through an equally thick layer of snow.


6.    (24353-!-item-!-188;#058&001207)


Which of the following most logically completes the passage?


Garnet and RenCo each provide health care for their employees.  Garnet pays for both testing of its employees' cholesterol levels and treatment of high cholesterol.  This policy saves Garnet money, since high cholesterol left untreated for many years leads to conditions that require very expensive treatment.  However, RenCo does not have the same financial incentive to adopt such a policy, because __________.


(A) early treatment of high cholesterol does not entirely eliminate the possibility of a stroke later in life
(B) the mass media regularly feature stories encouraging people to maintain diets that are low in cholesterol
(C) RenCo has significantly more employees than Garnet has
(D) RenCo's employees are unlikely to have higher cholesterol levels than Garnet's employees
(E) the average length of time an employee stays with RenCo is less than it is with Garnet


7.    (24401-!-item-!-188;#058&001291)


United Lumber will use trees from its forests for two products.  The tree trunks will be used for lumber and the branches converted into wood chips to make fiberboard.  The cost of this conversion would be the same whether done at the logging site, where the trees are debranched, or at United's factory.  However, wood chips occupy less than half the volume of the branches from which they are made.


The information given, if accurate, most strongly supports which of the following?


(A) Converting the branches into wood chips at the logging site would require transporting a fully assembled wood-chipping machine to and from the site.
(B) It would be more economical to debranch the trees at the factory where the fiberboard is manufactured.
(C) The debranching of trees and the conversion of the branches into chips are the only stages in the processing of branches that it would be in United's economic advantage to perform at the logging site.
(D) Transportation costs from the logging site to the factory that are determined by volume of cargo would be lower if the conversion into chips is done at the logging site rather than at the factory.
(E) In the wood-processing industry, branches are used only for the production of wood chips for fiberboard.


8.    (24449-!-item-!-188;#058&001338)


Which of the following most logically completes the argument?


Utrania was formerly a major petroleum exporter, but in recent decades economic stagnation and restrictive regulations inhibited investment in new oil fields.  In consequence, Utranian oil exports dropped steadily as old fields became depleted.  Utrania's currently improving economic situation, together with less-restrictive regulations, will undoubtedly result in the rapid development of new fields.  However, it would be premature to conclude that the rapid development of new fields will result in higher oil exports, because __________.


(A) the price of oil is expected to remain relatively stable over the next several years
(B) the improvement in the economic situation in Utrania is expected to result in a dramatic increase in the proportion of Utranians who own automobiles
(C) most of the investment in new oil fields in Utrania is expected to come from foreign sources
(D) new technology is available to recover oil from old oil fields formerly regarded as depleted
(E) many of the new oil fields in Utrania are likely to be as productive as those that were developed during the period when Utrania was a major oil exporter

fox0923

今天是bible的例题分析，解释的非常清楚，大家要仔细看啊~

The stimulus is prefaced by the word “advertisement.” One quirk of the LSAT
is that every stimulus in LSAT history that has been preceded by this word has
contained faulty or deceptive logic. Thus, whenever you see this word
prefacing a stimulus, be on the lookout for misleading or flawed reasoning.
The argument is constructed as follows:
Premise: At most jewelry stores, the person assessing the diamond is
the person selling it.
Premise/Sub-conclusion:
So you can see why an assessor might say that a diamond is
of higher quality than it really is.
Premise: All diamonds sold at Gem World are certified in writing,
Conclusion: You’re assured of a fair price when purchasing a diamond
from Gem World.

The first sentence contains a premise and conclusion that relies on the
assumption that financial motivation might cause a person to lie about the
quality of the item. According to the advertisement, at Gem World there is no
such worry because the diamonds are certified in writing. Think for a
moment—does that reasoning sound bulletproof? If you were standing there in
the store and you were told that Gem World has written certification, wouldn’t
you ask who does the certification? This is the essence of personalizing the
argument—place yourself inside the situation and think how you would react.
As soon as you do that in this question, the weakness in the argument becomes
apparent. Then, since this is a Strengthen question, you can look for an answer
choice that eliminates this weakness. Answer choice (E) addresses the hole in
the argument by indicating that the individuals who provide the written
certification are not the same people who are selling the diamonds at Gem
World.
There are other errors in the stimulus, such as assuming that a written
certification equals a fair price. The certification may have no impact on the
actual price of the diamond, or perhaps it could even be used to raise the price
unjustly. These problems are ignored by the answer choices, and the test makers
have that right.
Answer choice (A): The conclusion addresses the fair price of diamonds at
Gem World, not other stores. Hence, the fact that other stores have written
certification does not help the Gem World advertisement.
Answer choice (B): This is an answer many people keep as a Contender. The
answer is incorrect because it fails to address the point raised in the first
sentence, namely that the person assessing the diamond has a personal stake in
the outcome. This “accountability” issue is the central point of the argument,
and without knowing the source of the certifications, this answer does not
strengthen the argument.
Answer choice (C): The argument asserts that a fair price is assured when
purchasing a diamond at Gem World. No claim to comparative quality is made
in the advertisement, and thus this answer does not strengthen the argument.
Answer choice (D): If anything, this answer may hurt the argument since it
indicates that a fair price may not be obtainable at Gem World due to price
volatility. If prices change daily, then Gem World may be selling diamonds at a
price that does not reflect current market value. However, the answer choice
specifically mentions “the most expensive diamonds” and there is no guarantee
that Gem World carries diamonds in this price range. So, at best, the answer
choice has no effect on the argument and is therefore incorrect.
Answer choice (E): This is the correct answer. As mentioned above, this answer
addresses the separation of the certification writer from the seller and thereby
strengthens the reasoning.





PREP CR KEY: AEDB

daisyの小夢想

哇呼呼。时间过得真快，期待勤奋的战友们入群~

fox0923

精练----------------------31s---------------------------strengthenP: The person who assess the diamond is the one sell it to you, we could know that these people value the diamond higher than it really is.
P: All the sold diamonds are certified in writing.
C: So the price of diamond will be fair for us.
Prephrase: People who write the certification of these diamonds in Gem world are not people who assess the value of diamonds.


Analysis:
(A) Many jewelry stores other than Gem World also
provide written certification of the quality of
their diamonds.-------------------------------------------------We don't care about other stores, we care if the value and price of diamonds are fair.
(B) The certifications of diamonds at Gem World
are written by people with years of
experience in appraising gems.------------------------------this can be the contender to eliminate our doubt. 我给选错了，在B/E中徘徊，然后B实际上是重复了premise，虽然加了year of experience，但是不能说明这些人就qualify了。
(C) The diamonds sold at Gem World are generally
of higher quality than those sold at other
jewelry stores.--------------------------------------------------higher quality doesn't mean fair price.
(D) The diamond market is so volatile that prices of
the most expensive diamonds can change by
hundreds of dollars from one day to the next.------------weaken the conclusion somewhat.
(E) The written certifications of diamonds at Gem
World are provided by an independent
company of gem specialists.---------------------------------whether the company or person writes this certification is not important, the issue is whether the company or person is qualified to write the certification.As mentioned above, this answer addresses the separation of the certification writer from the seller and thereby strengthens the reasoning.


---------------------------------------------------------------------------------------------------------------------------------------------
小总结一下：
1. 看到了advertisment这类的内容，就要联想到这个argument有flaw；
2. 把自己置身于场景中，然后问自己：If you were standing there in the store and you were told that Gem World has written certification, wouldn’t you ask who does the certification?
这种方法没有尝试过，下次做题的时候试试看。
3. strengthen问题可以去掉有可能weaken argument的choice--〉since this is a Strengthen question, you can look for an answer choice that eliminates this weakness. 这里和我起初想象的事一样的。
4. 其他的prephrase：There are other errors in the stimulus, such as assuming that a written certification equals a fair price.
The certification may have no impact on the actual price of the diamond, or perhaps it could even be used to raise the price unjustly.
我自己肯定想不到这么多~~
5. 改错~~B/E

zz42050524

哇呼呼。时间过得真快，期待勤奋的战友们入群~

-- by 会员 daisyの小夢想 (2011/12/9 0:05:01)

快啦，快啦，马上这一期做完就能入群啦~~~~

zz42050524

2011/12/9 support 33s
At most jewelry stores, people who sell the jewelry assess it, so assessor says that the jewelry is higher the quality than it real is.
People in A store can get the jewelry in its real value.
Pre: 在大多数商店和A商店买珠宝会有不同的结果，前提解释了大多数商店的原因，那么答案是就是Astore和大多数商店估价不同，以导致来了A不同的效果，增强结论。
(A) Many jewelry stores other than Gem World also    这个似乎是一个weaken，其实是无关，前提突出的是
provide written certification of the quality of           估价者是卖者这层有利益关系的评估
their diamonds.
(B) The certifications of diamonds at Gem World       似乎是support，其实没有，没有契合到突出点
are written by people with years of
experience in appraising gems.
(C) The diamonds sold at Gem World are generally     irrelevant
of higher quality than those sold at other
jewelry stores.
(D) The diamond market is so volatile that prices of    irrelevant
the most expensive diamonds can change by
hundreds of dollars from one day to the next.
(E) The written certifications of diamonds at Gem     这是一个support，是答案，突出了估价者和珠宝的
World are provided by an independent                销售无利益关系。
company of gem specialists.

qiuhua01234567

入群，入群
Background: Manufacturers sometimes discount the price of a product to retailers for a promotion period
when the product is advertised to consumers

Premise: Such promotions often result in a dramatic
increase in amount of product sold by the manufacturers to retailers

conclusion the
manufacturers could often make more profit by not holding the promotions.

(A)The amount of discount generally offered by manufacturers to retailers is carefully
calculated to represent the minimum needed to draw consumers' attention to the product.
(B) For many consumer products the period of advertising discounted prices to consumers is
about a week, not sufficiently long for consumers to become used to the sale price.
(C) For products that are not newly introduced, the purpose of such promotions is to keep
the products in the minds of consumers and to attract consumers who are currently using
competing products.
(D) During such a promotion retailers tend to accumulate in their warehouses inventory
bought at discount; they then sell much of it later at their regular price.

-----------------------------------------------------------------------------------------correct
(E) If a manufacturer fails to offer such promotions but its competitor offers them, that
competitor will tend to attract consumers away from the manufacturer's product.



Background：Researcher: People with certain personality disorders have more theta brain waves than those without such disorders

Premise: my data show that the amount of one’s theta brain waves increases while watching TV

Conclusion: watching too much TV increases one’s risk of developing personality disorders

(A)uses the phrase “personality disorders” ambiguously

(B) fails to define the phrase “theta brain waves”

(C) takes a correlation to imply a causal connection

----------------------------------------------------------------------------correct.
(D) draws a conclusion from an unrepresentative sample of data
(E) infers that watching TV is a consequence of a personality disorder
2.background: Excavation of the ancient city of Kourion on the island
of Cyprus revealed a pattern of debris and collapsed buildings typical of towns devastated by earthquakes.
Conclusion: destruction was due to a major earthquake known to have occurred near the island in A.D. 365

(A)Bronze ceremonial drinking vessels that are often found in graves dating from years preceding and following A.D. 365 were also found in several graves near Kourion.

(B) No coins minted after A.D. 365 were found in Kourion, but coins minted before that year were found in abundance.

---------------------------------------------------------------------------------------------------------correct
(C) Most modern histories of Cyprus
mention that an earthquake occurred near the island in A.D. 365.
(D) Several small statues carved in styles current in Cyprus in the century between A.D. 300 and 400 were found in Kourion.
(E) Stone inscriptions in a form of the Greek alphabet that was definitely used in Cyprus after A.D. 365 were found in Kourion.
Background: According to a review of 61 studies of patients suffering from severely debilitating depression, a large majority of the patients reported that missing a night's sleep immediately lifted their depression

Conclusion: Yet sleep-deprivation is not used to treat depression even though the conventional treatments, which use drugs and electric shocks, often have serious side effects.

(A)For a small percentage of depressed patients, missing a night's sleep induces a temporary sense of euphoria.
(B) Keeping depressed patients awake is more difficult than keeping awake people who are not depressed.
(C) Prolonged loss of sleep can lead to temporary impairment of judgment comparable to that induced by consuming several ounces of alcohol.
(D) The dramatic shifts in mood connected with sleep and wakefulness have not been traced to particular changes in brain chemistry.
(E) Depression returns in full force as soon as the patient sleeps for even a few minutes.

-------------------------------------------------------------------------------------------------------------correct

Background: In many corporations, employees are being replaced by automated equipment in order to save money

Conclusion: many workers who lose their jobs to automation will need government assistance to survive, and the same corporations that are laying people off will eventually pay for that assistance through increased taxes and unemployment insurance payments.

(A)Many workers who have already lost their jobs to automation have been unable to find new jobs.

--------------------------------------------------------------------------------------------------------------correct
(B) Many corporations that have failed to automate have seen their profits decline.
(C) Taxes and unemployment insurance are paid also by corporations that are not automating.
(D) Most of the new jobs created by automation pay less than the jobs eliminated by automation did.
(E) The initial investment in machinery for automation is often greater than the short-term savings in labor costs.

Background: United States
hospitals have traditionally relied primarily on revenues from paying patients to offset losses from unreimbursed care
(A)Although the advance of technology has made expensive medical procedures available to the wealthy, such procedures are out of the reach of low-income patients.
(B) If hospitals do not find ways of raising additional income for unreimbursed care, they must either deny some of that care or suffer losses if they give it.

--------------------------------------------------------------------------------------------------------correct
(C) Some patients have incomes too high for eligibility for governmental health insurance but are unable to afford private insurance for hospital care.
(D) If the hospitals reduce their costs in providing care, insurance companies will maintain the current level of reimbursement, thereby providing more funds for unreimbursed care.
(E) Even though philanthropic donations have traditionally provided some support for the hospitals, such donations are at present declining.

Background：At most jewelry stores, the person assessing the diamond is the person selling it so
you can see why an assessor might say that a diamond is of higher quality than it really is.

Premise：all diamonds sold at Gem World are certified in writing

Conclusion：you’re assured of a fair price when purchasing a diamond from Gem
World.

(A)Many jewelry stores other than Gem World also
provide written certification of the quality of
their diamonds.
(B) The certifications of diamonds at Gem World
are written by people with years of
experience in appraising gems.
(C) The diamonds sold at Gem World are generally
of higher quality than those sold at other
jewelry stores.
(D) The diamond market is so volatile that prices of
the most expensive diamonds can change by
hundreds of dollars from one day to the next.
(E) The written certifications of diamonds at Gem
World are provided by an independent
company of gem specialists.

----------------------------------------------------------correct

Background: Microscopic plants called algae grow inside the top layer of sea ice in the Antarctic if enough sunlight reaches that layer of ice and enough seawater, which contains nutrients, reaches that layer after splashing onto the surface

Conclusion:  Even though moderate snow cover reduces the sunlight that filters into the top layer, sea ice with moderate snow cover typically contains even more algae in the top layer than does sea ice with less snow cover.



(A) As the weight of accumulated snow forces ice lower in the water, more seawater splashes onto the surface and seeps through the snow.

-------------------------------------------------------------------------------------------correct

(B) Seawater in the Antarctic often contains higher concentrations of nutrients than does seawater in more temperate regions.
(C) As the air temperature around sea ice decreases during the winter, the likelihood decreases that snow will fall and thus add to any existing snow cover.
(D) The nutrients on which algae rely are common in seawater throughout the Antarctic.
(E) More sunlight filters through a layer of ice than through an equally thick layer of snow.
background: Garnet and RenCo each provide health care for their employees.  Garnet pays for both testing of its employees' cholesterol levels and treatment of high cholesterol.

Premise: This policy saves Garnet money, since high cholesterol left untreated for many years leads to conditions that require very expensive treatment

Conclusion: RenCo does not have the same financial incentive to adopt such a policy
(A) early treatment of high cholesterol does not entirely eliminate the possibility of a stroke later in life
(B) the mass media regularly feature stories encouraging people to maintain diets that are low in cholesterol
(C) RenCo has significantly more employees than Garnet has
(D) RenCo's employees are unlikely to have higher cholesterol levels than Garnet's employees
(E) the average length of time an employee stays with RenCo is less than it is with Garnet

-----------------------------------------------------------------------------------------------correct



(A) Converting the branches into wood chips at the logging site would require transporting a fully assembled wood-chipping machine to and from the site.
(B) It would be more economical to debranch the trees at the factory where the fiberboard is manufactured.
(C) The debranching of trees and the conversion of the branches into chips are the only stages in the processing of branches that it would be in United's economic advantage to perform at the logging site.
(D) Transportation costs from the logging site to the factory that are determined by volume of cargo would be lower if the conversion into chips is done at the logging site rather than at the factory.

--------------------------------------------------------------------------------correct

Background: Utrania was formerly a major petroleum exporter, but in recent decades economic stagnation and restrictive regulations inhibited investment in new oil fieldsIn consequence, Utranian oil exports dropped steadily as old fields became depleted.  Utrania's currently improving economic situation, together with less-restrictive regulations, will undoubtedly result in the rapid development of new fields

Conclusion: it would be premature to conclude that the rapid development of new fields will result in higher oil exports

(A)the price of oil is expected to remain relatively stable over the next several years
(B) the improvement in the economic situation in Utrania is expected to result in a dramatic increase in the proportion of Utranians who own automobiles
(C) most of the investment in new oil fields in Utrania is expected to come from foreign sources
(D) new technology is available to recover oil from old oil fields formerly regarded as depleted

------------------------------------------------------------------------------correct
(E) many of the new oil fields in Utrania are likely to be as productive as those that were developed during the period when Utrania was a major oil exporter
看错，悔

fox0923

哇呼呼。时间过得真快，期待勤奋的战友们入群~

-- by 会员 daisyの小夢想 (2011/12/9 0:05:01)

快啦，快啦，马上这一期做完就能入群啦~~~~

-- by 会员 zz42050524 (2011/12/9 9:33:38)

恩恩，快啦快啦

winghyy

精炼题
45s-strengthen
At most jewelry store, the person who assess the diamond is the person who sell it. That's why an assessor say that a diamond is of higher quaility than it is. At Gem World, all diamond sold are certified in writing, so you can get a fair price.
Prephase: The assessor is from a independent certified authority.
选E
(A) Many jewelry stores other than Gem World also provide written certification of the quality of
their diamonds. ——weaken, Gem world has no advantage.
(B) The certifications of diamonds at Gem World are written by people with years of
experience in appraising gems.——tricky, these people can also be a employee of GEM
(C) The diamonds sold at Gem World are generally of higher quality than those sold at other
jewelry stores.—— irrelevant (high quality)
(D) The diamond market is so volatile that prices of the most expensive diamonds can change by
hundreds of dollars from one day to the next.——irrelevant (the whole market)
(E) The written certifications of diamonds at Gem World are provided by an independent
company of gem specialists. ——bingo

winghyy

逻辑链
5.55s-discrepancy
Algae grow when enough sunlight reaches the layer of ice and enough seawater reach that layer.
Seaice with moderate snow cover contains more algae than with less snow cover, although moderate snow cover reduces the sunlight.
Prephase： moderate snow cover keep a stable temperature, with the same effect of sunlight.
选A

6.46s-complete(because)
G pays for both testing of C levels and treatment of C. This policy help G save money, since the treatment cost is very high.
But R does not adopt this policy, because_______
Prephase: R company buy an health insurance for every employee.
选E

7. 80s-support the following (must be true)
United Lumber use trees for two products. Tree truncks will be used for lumbers and the branch will be converted into wood chips. The cost of the convertion will be the same at the different place. However, wood chips occupy less than half the volumn of the branches.
选A

8. 45s-complete (because)
U is improving economic situation, together with less restrictive regulations. It will result in the rapid development of new fields. However, it would be premature to conclude that the development of new fields will result in higher oil exports,because____
Prephase: The oil drilled from the new field can not meet the needs of local market.
选B