GWD 逻辑－有我自己的理解－大家都来看看一起讨论吧

第６套

Q22:

The violent crime rate (number of violent crimes per 1,000 residents) in Meadowbrook is 60 percent higher now than it was four years ago.  The corresponding increase for Parkdale is only 10 percent.  These figures support the conclusion that residents of Meadowbrook are more likely to become victims of violent crime than are residents of Parkdale.

The argument above is flawed because it fails to take into account

1. changes in the population density of both Parkdale and Meadowbrook over the past four years
2. how the rate of population growth in Meadowbrook over the past four years compares to the corresponding rate for Parkdale
3. the ratio of violent to nonviolent crimes committed during the past four years in Meadowbrook and Parkdale
4. the violent crime rates in Meadowbrook and Parkdale four years ago
5. how Meadowbrook’s expenditures for crime prevention over the past four years compare to Parkdale’s expenditures

   Answer:Ｄ

削弱题。

暴力犯罪率（每千人暴力犯罪数量）在Ｍ比４年前高６０％。而在Ｐ地区，相应的增长仅为１０％。结论：该数字表明Ｍ地区的居民比Ｐ地区的居民更容易遭受暴力犯罪的威胁。

错选Ａ。不是很明白。是不是因为是千人犯罪率，所以与人口密度无关？与Ｂ一样的道理？

B因为题目中说明是千人犯罪率，所以与人口增长率无关。

Ｃ无关，与non-violent crimes无关。

D,如果暴力犯罪率以前在Ｍ地区很低，几乎没有，而在Ｐ地区本来就非常高，那么Ｍ地区有可能增长６０％之后的暴力犯罪率还是比增长了１０％的暴力犯罪率的Ｐ地区人们遭受暴力犯罪威胁的可能性要低。

E无关。

－－－－－－－－

第１３套

By competing with rodents for seeds, black ants help control rodent populations that pose a public health risk.  However, a very aggressive species of blank ant, the Loma ant, which has recently invaded a certain region, has a venomous sting that is often fatal to humans.  Therefore, the planned introduction into that region of ant flies, which prey on Loma ants, would benefit public health.

Which of the following, if true, most strengthens the argument?

A.     Ant flies do not attack black ants other than Loma ants.

2. Loma ants are less effective than many bird species in competing with rodents for seeds.
3. Certain other species of black ants are more effective than Loma ants in competing with rodents for seeds.
4. The sting of Loma ants can also be fatal to rodents.
5. The use of pesticides to control Loma ants could have harmful effects on the environment.

   Answer: A

加强题。

好像明白好像不明白的。

错选E, 错选两次。因为后面一句说would benefit public health，所以才选择的E. 不是很理解为什么选择A.

Q13:

In the United States, of the people who moved from one state to another when they retired, the percentage who retired to Florida has decreased by three percentage points over the past ten years.  Since many local businesses in Florida cater to retirees, this decline is likely to have a noticeably negative economic effect on these businesses.

Which of the following, if true, most seriously weakens the argument?

1. Florida attracts more people who move from one state to another when they retire than does any other state.
2. The number of people who move out of Florida to accept employment in other states has increased over the past ten years.
3. There are far more local businesses in Florida that cater to tourists than there are local businesses that cater to retirees.
4. The total number of people who retired and moved to another state for their retirement has increased significantly over the past ten years.
5. The number of people who left Florida when they retired to live in another state was greater last year than it was ten years ago.

   Answer: D

削弱题。

错选AE.但是还是没有太理解为什么错。参考了网友的解释，但是还是不是很理解。

网友给的解释：

错选为A   A是无关，D的意思是，即使比例下降了，但绝对数上升了，所以这些生意还是好的。而且是和佛州本身比，不是和其它州比，A错。本题考察numbert and percentage，GMAT的一大类题。

I used TTGWD,so cannot find the regular common sequence the forum used. Sure I did searched before. Because it is more effient if I find the result by myself than by waiting for others' answer. The forum does not authorize us to search via content. It is not that convenient.

Well, thank you all the same