GRE真题6

Each of six automated tasks, numbered 1 through 6, takes one full hour to　complete. No time elapses between the completion of any of the six tasks and　the beginning of another task. The group of six tasks must be completed in the　shortest possible time period, subject only to the following restrictions:　

Tasks 1 and 2 must both be completed before any of the other tasks can be begun.
Task 3 must be completed before task 4 can be begun.
At any one time, no more than one task can be performed, except that tasks 4　and 5 can be performed concurrently.

Which of the following tasks could be the second task performed?
2
3
4
5
6
答案：(A)
The shortest possible time period in which the group of six tasks can be　completed is
two hours
three hours
four hours
five hours
six hours
答案：(D)

Which of the following CANNOT be true of any acceptable ordering of tasks?
Task 1 is performed before task 2.
Task 3 is performed before task 6.
Task 4 is performed before task 6.
Task 5 is performed before task 3.
Task 6 is performed before task 3.
答案：(D)

If task 6 is performed as early in the order of tasks as is permissible, then　task 6 is performed
first
second
third
fourth
fifth
答案：(C)

Most television viewers estimate how frequently a particular type of accident　or crime occurs by how extensively it is discussed on television news shows.Television news shows report more on stories that include dramatic pictures such　as fires and motor vehicle accidents than they do on more common stories that　have little visual drama such as bookkeeping fraud.　

If the statements above are true, it can be properly concluded that which of　the following is also true?

The time that television news reporters spend researching news stories is　　directly related to the number of viewers who will be affected by events like　　those in the news stories.

It is easier for crimes such as bookkeeping fraud to go unprosecuted than it　is for crimes such as arson.

The number of fires and motor vehicle accidents greatly increases after each　television news show that includes dramatic pictures of a fire or motor vehicle　accident.

Viewers of television news shows tend to overestimate the number of fires　and motor vehicle accidents that occur relative to the number of crimes of　bookkeeping fraud.

The usual selection of news stories for television news shows is determined　by the number of news reporters available for assignment.

答案：(D)
问题：如果上面的陈述正确，则能够推断出下面哪一个一定正确？

读题：许多电视观众通过一种特定事故或犯罪在电视新闻上被讨论的广阔性来估计其发生的频率。电视新闻报道包含象开枪射击或汽车事故等生动场面的事情比包含象偷书等不带有视觉效果的事情要多。

C. 当包含象开枪射击或汽车事故等场面的新闻被报道之后，开枪或汽车事故的数目将大大增加。（原文中说的是，观众根据事故被讨论的广阔性来估计其发生的频率。但是是不是实际上也是这样发生的，你是不知道的,所以C不对）

According to one psychological theory, in order to be happy, one must have an　intimate relationship with another person. Yet the world s greatest composers　spent most of their time in solitude and had no intimate relationships. So the　psychological theory must be wrong.　

The conclusion above assumes that

the world s greatest composers chose to avoid intimate relationships
people who have intimate relationships spend little time in solitude
solitude is necessary for the composition of great music
less well known composers had intimate relationships
the world s greatest composers were happy
答案：(E)

Every member of the Progress party in a certain city council voted against　appropriating funds to build a new bridge. All city council members voted on　the bridge-appropriation issue. A simple majority of votes was needed to pass　the bill.　

Which of the following statements, if true, would provide sufficient　information to tell whether or not the bridge appropriation bill passed?

The Progress party holds a majority of seats on the city council.

Less than half of the members of the other parties all taken together voted　against the bridge appropriation.

No other Council Members voted against the bridge appropriation.

Three-fourths of the votes cast against the appropriation were by members of　the Progress party.

Every member of the city council is either a member of the Popular party or a　member of the Progress party.

答案：(A)

An office is one of several in which all the furniture is to be repainted.The office contains exactly four pieces of furniture-a bookcase, two chairs, and　a desk-and no furniture is to be moved into or out of that office. The　repainting specifications are as follows:　

On completion of repainting, any piece of furniture in an office must be　uniformly brown, green, tan, or white.

On completion of repainting, at least one of the pieces of furniture in an　office must be green, and the desk must be either brown or tan.

If, prior to repainting, a piece of furniture is either orange or yellow, that　piece must be white on completion of repainting.

If, prior to repainting, a piece of furniture is tan, that piece must remain　tan on completion of repainting.

All of the specifications above can and must be met in each office scheduled　for repainting,

Which of the following could be the furniture colors in the office on　completion of repainting?

Bookcase 　Chair 　Chair 　Desk

Yellow Brow White Tan
White Green Green Brown
Green White Orange Brown
Brown Tan White Tan
Tan White Brown Green
答案：(B)
读题：办公室重漆家具，共有4件家具：1B(bookcase)，2C(chairs)，1D(desk)

写条件：
1、油漆完后每件家具颜色是b(brown),g(green),t(tan),w(white)中的一种。
2、g≥1,D=b/t (表示重漆之后，至少有一件家具是g, desk变为b或者t)
3、o,y → w (表示重漆之前的o或y, 重漆之后变为w)
4、t → t (表示重漆之前的t，重漆之后还是t)　
条件总结：

*g≥1是一个全局性限制条件，它对整个重画作出了一种限制，无论你在什么情况下都必须要满足它，象这种对全局，对整体限制的条件始终是解题的重点。相对来说，D=b/t只是对Desk这了某种限制，是一个局部条件。
If, prior to repainting, one chair in the office is orange and the other chair　is tan, which of the following must be true of the furniture in the office on　completion of repainting?

The bookcase is green.
Exactly one of the chairs is brown.
Exactly one of the chairs is orange.
Both of the chairs are white.
The desk is tan.
答案：(A)

如果重漆之前，两个C为o,t, 下面哪一个在重漆之后must be true?
解题步骤：
1、C为o,t
条件3：o,y→w， ∴重漆之后一件C为w
条件4：t→t， ∴重漆之后另一件C为t
2、重漆之后的条件还有，g≥1, D=b/t,
所以只有B为green