几道做了几遍都不明白的逻辑题

apple003

DX能给我解释一下各个选项吗？
1、. Seven countries signed a treaty binding each of them to perform specified actions on a certain fixed date, with the actions of each conditional on simultaneous action taken by the other countries. Each country was also to notify the six other countries when it had completed its action.
The simultaneous-action provision of the treaty leaves open the possibility that（答案E）
(A) the compliance date was subject to postponement, according to the terms of the treaty
(B) one of the countries might not be required to make any changes or take any steps in order to comply with the treaty, whereas all the other countries are so required.
(C) each country might have a well-founded excuse, based on the provision, for its own lack of compliance
(D) the treaty specified that the signal for one of the countries to initiate action was notification by the other countries that they had completed action
(E) there was ambiguity with respect to the date after which all actions contemplated in the treaty are to be complete.
2. A recent report determined that although only three percent of drivers on Maryland highways equipped their vehicles with radar detectors, thirty-three percent of all vehicles ticketed for exceeding the speed limit were equipped with them. Clearly, drivers who equip their vehicles with radar detectors are more likely to exceed the speed limit regularly than are drivers who do not.
The conclusion drawn above depends on which of the following assumptions? 答案B
(A) Drivers who equip their vehicles with radar detectors are less likely to be ticketed for exceeding the speed limit than are drivers who do not. (B) Drivers who are ticketed for exceeding the speed limit are more likely to exceed the speed limit regularly than are drivers who are not ticketed.
(C) The number of vehicles that were ticketed for exceeding the speed limit was greater than the number of vehicles that were equipped with radar detectors.
(D) Many of the vehicles that were ticketed for exceeding the speed limit were ticketed more than once in the time period covered by the report.
(E) Drivers on Maryland highways exceeded the speed limit more often than did drivers on other state highways not covered in the report.
3.Blood banks will shortly start to screen all donors for NANB hepatitis. Although the new screening tests are estimated to disqualify up to 5 percent of all prospective blood donors, they will still miss two-thirds of donors carrying NANB hepatitis. Therefore, about 10 percent of actual donors will still supply NANB-contaminated blood.
The argument above depends on which of the following assumptions? 答案A
(A)Donors carrying NANB hepatitis do not,in a large percentage of cases, carry other infections for which reliable screening tests are routinely performed.
(B) Donors carrying NANB hepatitis do not,in a large percentage of cases, develop the disease themselves at any point.
(C) The estimate of the number of donors who would be disqualified by tests for NANB hepatitis is an underestimate.
(D) The incidence of NANB hepatitis is lower among the potential blood donors than it is in the population at large.
(E) The donors who will still supply NANB-contaminated blood will donate blood at the average frequency for all donors.
4.In the United States, vacationers account for more than half of all visitors to what are technically called "pure aquariums" but for fewer than one quarter of all visitors to zoos, which usually include a "zoo aquarium" of relatively modest scope.
Which of the following, if true, most helps to account for the difference described above between visitors to zoos and visitors to pure aquariums? 答案B
(A) In cities that have both a zoo and a pure aquarium, local residents are twice as likely to visit the aquarium as they are to visit the zoo.
(B) Virtually all large metropolitan areas have zoos,whereas only a few large metropolitan areas have pure aquariums.
(C) Over the last ten years,newly constructed pure aquariums have outnumbered newly established zoos by a factor of two to one.
(D) People who visit a zoo in a given year are two times more likely to visit a pure aquarium that year than are people who do not visit a zoo.
(E) The zoo aquariums of zoos that are in the same city as a pure aquarium tent to be smaller than the aquariums of zoos that have no pure aquarium nearby.
5.Which of the following, if true, is the most logical completion of the argument below? 答案a
The tax system of the Republic of Grootland encourages borrowing by granting its taxpayers tax relief for interest paid on loans. The system also discourages saving by taxing any interest earned on savings. Nevertheless, it is clear that Grootland's tax system does not consistently favor borrowing over saving, for if it did, there would be no--.
(A) tax relief in Grootland for those portions of a taxpayer's income, if any, hat are set aside to increase that taxpayer's total savings
(B) tax relief in Grootland for the processing fees that taxpayers pay to ending institutions when obtaining certain kinds of loans
(C) tax relief in Grootland for interest that taxpayers are charged on the unpaid balance in credit card accounts
(D) taxes due in Grootland on the cash value of gifts received by taxpayers from banks trying to encourage people to open saving accounts
(E) taxes due in Grootland on the amount that a taxpayer has invested in interest-bearing savings accounts

6、 The average age of chief executive officers (CEO's) in a large sample of companies is 57. The average age of CEO's in those same companies 20 years ago was approximately eight years younger. On the basis of those data, it can be concluded that CEO's in general tend to be older now.
Which of the following casts the most doubt on the conclusion drawn above? 答案C
(A) The dates when the CEO's assumed their current positions have not been specified.
(B) No information is given concerning the average number of years that CEO's remain in office.
(C) The information is based only on companies that have been operating for at least 20 years.
(D) Only approximate information is given concerning the average age of the CEO's 20 years ago.
(E) Information concerning the exact number of companies in the sample has not been given.
Surveys show that every year only 10 percent of cigarette smokers switch brands. Yet the manufacturers have been spending an amount equal to 10 percent of their gross receipts on cigarette promotion in magazines. It follows from these figures that inducing cigarette smokers to switch brands did not pay, and that cigarette companies would have been no worse off economically if they had dropped their advertising.
7. Of the following, the best criticism of the conclusion that inducing cigarette smokers to switch brands did not pay is that the conclusion is based on   答案E
(A) computing advertising costs as a percentage of gross receipts, not of overall costs
(B) past patterns of smoking and may not carry over to the future
(C) the assumption that each smoker is loyal to a single brand of cigarettes at any one time
(D) the assumption that each manufacturer produces only one brand of cigarettes
(E) figures for the cigarette industry as a whole and may not hold for a particular company

apple003

有人帮忙吗

oldreaper

以下是引用apple003在2003-9-8 10:16:00的发言：
DX能给我解释一下各个选项吗？
2. A recent report determined that although only three percent of drivers on Maryland highways equipped their vehicles with radar detectors, thirty-three percent of all vehicles ticketed for exceeding the speed limit were equipped with them. Clearly, drivers who equip their vehicles with radar detectors are more likely to exceed the speed limit regularly than are drivers who do not.
The conclusion drawn above depends on which of the following assumptions? 答案B
  (A) Drivers who equip their vehicles with radar detectors are less likely to be ticketed for exceeding the speed limit than are drivers who do not. (B) Drivers who are ticketed for exceeding the speed limit are more likely to exceed the speed limit regularly than are drivers who are not ticketed.
(C) The number of vehicles that were ticketed for exceeding the speed limit was greater than the number of vehicles that were equipped with radar detectors.
(D) Many of the vehicles that were ticketed for exceeding the speed limit were ticketed more than once in the time period covered by the report.
(E) Drivers on Maryland highways exceeded the speed limit more often than did drivers on other state highways not covered in the report.

http://forum.chasedream.com/dispbbs.asp?boardID=24&ID=12114

apple003

非常感谢！不知道其他题以前是否讨论过？

jubel

1。题目大意是说七个国家约定某天干某事，条件是其他六个都干了。这里完成日期就有两个，一个是”某天“，一个是其他六个都完成的时候，从而有歧义。
3。如果NANB捐血者还有别的会被查处的毛病，那么NANB测试剩下的10％中还会有些人由于那些别的测试而被筛掉，从而最终剩下的就不到10％了。

shrkl

刚看了第一题，好难。
感觉是条约规定了action开始的时间，大家一起开始，但没有规定action完成时间，所以国家可以等其他国家完成之后在完成。所以只有E提出了这个缺陷。

3题是老题了，我是这样理解的， 条件是新机器可以查到upto 检验的5%得乙肝血，但还是漏掉2/3。（所以5%是1/3的乙肝）推出剩下的10％中还有乙肝。 可以看到10%恰恰好是漏掉的2/3。 所以10%一定没有其他的原因被排除。这也是答案中插入in a large percentage of cases的原因

4题是xdf 讲过。城市有纯海洋馆和动物园内的海洋馆。去纯海洋馆的旅游者多。答案解释说很多地方没有纯海洋馆，所以在有纯海洋馆的地方游客多

jq_jou

:-)