Hard CR questions involving proportion/numbers/statistics

Hello all.
This is the first of the collection of topic wise questions I am going to make here. This is a topic that hovers in the region where the quant part of the GMAT and the verbal part of the GMAT collide.
So try to solve the questions under 2.5 minutes and I will post the OAs in 2-3 days! You are free to google though!
Hopefully this set will help you clarify the doubts in this type of questions and leave no room for errors on the test day.

1. 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?

A. Florida attracts more people who move from one state to another when they retire than does any other state.
B. The number of people who move out of Florida to accept employment in other states has increased over the past ten years.
C. There are far more local businesses in Florida that cater to tourists than there are local businesses that cater to retirees.
D. The total number of people who retired and moved to another state for their retirement has increased significantly over the past ten years.
E. 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.

2. 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

A. changes in the population density of both Parkdale and Meadowbrook over the past four years
B. how the rate of population growth in Meadowbrook over the past four years compares to the corresponding rate for Parkdale
C. the ratio of violent to nonviolent crimes committed during the past four years in Meadowbrook and Parkdale
D. the violent crime rates in Meadowbrook and Parkdale four years ago
E. how Meadowbrook’s expenditures for crime prevention over the past four years compare to Parkdale’s expenditures

3. In Kravonia, the average salary for jobs requiring a college degree has always been higher than the average salary for jobs that do not require a degree. Over the last few years, the number of Kravonians enrolled in college has been growing steadily. Therefore, the number of Kravonians entering the job market who have at least the qualification of a college degree will eventuallty be significantly higher than it has been over the last few years.

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

A. Kravonians with more than one college degree earn little more, on average, than do Kravonians with only one college degree
B. The average number of years Kravonian college students remain enrolled before completing a degree has been increasing over the past several of years.
C. Despite the increase in the number of Kravonians attending college, the percentage of the population attending college is lower in Kravonia than in most other countries.
D. In recent years, empoyers have been requiring college degrees for workers in jobs that were previously performed successfully by Kravonians who did not have college degrees.
E. For many years, employers in Kravonia hva ehad difficulty finding enough college graduates to fill the high-paying jobs that were available.3

4. Because postage rates are rising, Home Decorator magazine plans to maximize its profits by reducing by one half the number of issues it publishes each year. The quality of articles, the number of articles published per year, and the subscription price will not change. Market research shows that neither subscribers nor advertisers will be lost if the magazine's plan is instituted.

Which of the following, if true, provides the strongest evidence that the magazine's profits are likely to decline if the plan is instituted?

A. With the new postage rates, a typical issue under the proposed plan would cost about one-third more to mail than a typical current issue would.
B. The majority of the magazine's subscribers are less concerned about a possible reduction in the quantity of the magazine's articles than about a possible loss of the current high quality of its articles.
C. Many of the magazine's long-time subscribers would continue their subscriptions even if the subscription price were increased.
D. Most of the advertisers that purchase advertising space in the magazine will continue to spend the same amount on advertising per issue as they have in the past.
E. Production costs for the magazine are expected to remain stable.

5. Corporate Officer: Last year was an unusually poor one for our chemical division, which has traditionally contributed about 60 percent of the corporation’s profits. It is therefore encouraging that there is the following evidence that the pharmaceutical division is growing stronger: it contributed 45 percent of the corporation’s profits, up from 20 percent the previous year.
On the basis of the facts stated, which of the following is the best critique of the evidence presented above?

(A) The increase in the pharmaceutical division’s contribution to corporation profits could have resulted largely from the introduction of single, important new product.
(B) In multidivisional corporations that have pharmaceutical divisions, over half of the corporation’s profits usually come from the pharmaceuticals.
(C) The percentage of the corporation’s profits attributable to the pharmaceutical division could have increased even if that division’s performance had not improved.
(D) The information cited does not make it possible to determine whether the 20 percent share of profits cited was itself an improvement over the year before.
(E) The information cited does not make it possible to compare the performance of the chemical and pharmaceutical divisions in of the percent of total profits attributable to each.

6. Political Advertisement: Mayor Delmont’s critics complain about the jobs that were lost in the city under Delmont’s leadership. Yet the fact is that not only were more jobs created than were eliminated, but the average pay for these new jobs has been higher than the average pay for jobs citywide every year since Delmont took office. So there can be no question that throughout Delmont’s tenure the average paycheck in this city has been getting steadily bigger.
Which of the following, if true, most strengthens the argument in the advertisement?

A. The average pay for jobs created in the city during the past three years was higher than the average pay for jobs created in the city earlier in Mayor Delmont’s tenure.
B. Average pay in the city was at a ten-year low when Mayor Delmont took office.
C. Some of the jobs created in the city during Mayor Delmont’s tenure have in the meantime been eliminated again.
D. The average pay for jobs eliminated in the city during Mayor Delmont’s tenure has been roughly equal every year to the average pay for jobs citywide.
E. The average pay for jobs in the city is currently higher than it is for jobs in the suburbs surrounding the city.

7. Denoma, a major consumer-electronics maker, had a sizeable decline in sales revenue for its most recent fiscal year. This result appears surprising, because electronics retailers report that although their overall sales were considerably lower than in the previous year, their sales revenue from Denoma models actually grew, largely thanks to some innovative and popular models that Denoma introduced.
Which of the following, if true, does most to explain the apparently surprising result?

A. Because of the need to educate the public about its new models’ capabilities, Denoma’s advertising spending was higher than normal over the period.
B. For the period at issue, Denoma’s major competitors reported declines in revenue that were, in percentage terms, greater than Denoma’s.
C. A significant proportion of Denoma’s revenue comes from making components for other consumer-electronics manufacturers.
D. Unlike some of its major competitors, Denoma has no lines of business outside consumer electronics to provide revenue when retail sales of consumer electronics are weak.
E. During the period, consumer-electronics retailers sold remaining units of Denoma’s superseded models at prices that were deeply discounted from those models’ original prices.

8. Twenty years ago, Balzania put in place regulations requiring operators of surface mines to pay for the reclamation of mined-out land. Since then, reclamation technology has not improved. Yet, the average reclamation cost for a surface coal mine being reclaimed today is only four dollars per ton of coal that the mine produced, less than half what it cost to reclaim surface mines in the years immediately after the regulations took effect.

Which of the following, if true, most helps to account for the drop in reclamation costs described?

A. Even after Balzania began requiring surface mine operators to pay reclamation costs, coal mines in Balzania continued to be less expensive to operate than coal mines in almost any other country.
B. In the twenty years since the regulations took effect, the use of coal as a fuel has declined from the level it was at in the previous twenty years.
C. Mine operators have generally ceased surface mining in the mountainous areas of Balzania because reclamation costs per ton of coal produced are particularly high for mines in such areas.
D. Even after Balzania began requiring surface mine operators to pay reclamation costs, surface mines continued to produce coal at a lower total cost than underground mines.
E. As compared to twenty years ago, a greater percentage of the coal mined in Balzania today comes from surface mines.

9. For the first time in history, more televisions than people can be found in American households. According to recent research, the average household has 2.55 residents and contains 2.73 televisions. However, by employing such costly manufacturing processes as plasma technology and flat screens, televisions are becoming too expensive for the typical consumer. As a result, the average number of residents per household will again surpass the number of televisions.

Which of the following, if true, most strongly supports the argument above?

A. House parties at which numerous individuals gather to view popular television shows on one television set have increased three hundred percent during the past year.
B. More than one million legal immigrants enter the United States each year.
C. New devices such as video-enabled personal digital assistants and music players are increasingly purchased for use as a primary source of information and entertainment.
D. As new technologies become more commonplace, manufacturing and retail costs normally decline.
E. As a result of technological advances, new televisions are increasingly enabled with some features, such as Internet browsing, traditionally associated with other household devices.