SDCAR2010【逻辑入门】（八）Assumptions

PhoebeQi

In the years following an eight-cent increase in the federal tax on a pack of cigarettes, sales of cigarettes fell ten percent. In contrast, in the year prior to the tax increase, sales had fallen one percent. The volume of cigarette sales is therefore strongly related to the after-tax price of a pack of cigarettes.

The argument above requires which of the following assumptions?

A)During the year following the tax increase, the pretax price of a pack of cigarettes did not increase by as much as it had during the year prior to the tax increase.
B)The one percent fall in cigarette sales in the year prior to tax increases was due to a smaller tax increase.
C)The pretax price of a pack of cigarettes gradually decreased throughout the year before and the year after the tax increase.
D)For the year following the tax increase, the pretax price of a pack of cigarettes was not eight or more cents lower than it had been the previous year.
E)As the after-tax price of a pack of cigarettes rises, the pretax price also rises.

I have no idea about it. I choose B. Thx for your help!

sdcar2010

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. Current enrollments in Kravonia's colleges indicate that over the next four years the percentage of the Kravonian workforce with college degrees will increase dramatically.  Therefore, the average salary for all workers in Kravonia is likely to increase over the next four years.
Which of the following is an assumption on which the argument depends?
A. Kravonians with more than one college degree earn more, on average, than do Kravonians with only one college degree.
B. The percentage of Kravonians who attend college in order to earn higher salaries is higher now than it was several years ago.
C. The higher average salary for jobs requiring a college degree is not due largely to a scarcity among the Kravonian workforce of people with a college degree.
D. The average salary in Kravonia for jobs that do not require a college degree will not increase over the next four years.
E. Few members of the Kravonian workforce earned their degrees in other countries.


i wonder "Therefore, the average salary for all workers in Kravonia is likely to increase over the next four years." should be the conclusion or the inference. thks

-- by 会员 twwzx (2012/5/3 10:36:56)

It is the conclusion.  Inference normally would not show up in the passage.  Further, there is only one conclusion in the passage anyway.

sdcar2010

In the years following an eight-cent increase in the federal tax on a pack of cigarettes, sales of cigarettes fell ten percent. In contrast, in the year prior to the tax increase, sales had fallen one percent. The volume of cigarette sales is therefore strongly related to the after-tax price of a pack of cigarettes.

The argument above requires which of the following assumptions?

A)During the year following the tax increase, the pretax price of a pack of cigarettes did not increase by as much as it had during the year prior to the tax increase.
B)The one percent fall in cigarette sales in the year prior to tax increases was due to a smaller tax increase.
C)The pretax price of a pack of cigarettes gradually decreased throughout the year before and the year after the tax increase.
D)For the year following the tax increase, the pretax price of a pack of cigarettes was not eight or more cents lower than it had been the previous year.
E)As the after-tax price of a pack of cigarettes rises, the pretax price also rises.

I have no idea about it. I choose B. Thx for your help!

-- by 会员 PhoebeQi (2012/5/3 11:44:38)

It is a math problem coupled with necessary assumption.

Use negation.

If you negate D), you have:
For the year following the tax increase, the pretax price of a pack of cigarettes WAS eight or more cents lower than it had been the previous year.

If this is true, then the final price of a pack of cigarettes did not change before and after the tax increase.  Accordingly, the conclusion of the passage is wrong.  Thus, D) is the necessary assumption.

twwzx

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. Current enrollments in Kravonia's colleges indicate that over the next four years the percentage of the Kravonian workforce with college degrees will increase dramatically.  Therefore, the average salary for all workers in Kravonia is likely to increase over the next four years.
Which of the following is an assumption on which the argument depends?
A. Kravonians with more than one college degree earn more, on average, than do Kravonians with only one college degree.
B. The percentage of Kravonians who attend college in order to earn higher salaries is higher now than it was several years ago.
C. The higher average salary for jobs requiring a college degree is not due largely to a scarcity among the Kravonian workforce of people with a college degree.
D. The average salary in Kravonia for jobs that do not require a college degree will not increase over the next four years.
E. Few members of the Kravonian workforce earned their degrees in other countries.


i wonder "Therefore, the average salary for all workers in Kravonia is likely to increase over the next four years." should be the conclusion or the inference. thks

-- by 会员 twwzx (2012/5/3 10:36:56)

It is the conclusion.  Inference normally would not show up in the passage.  Further, there is only one conclusion in the passage anyway.

-- by 会员 sdcar2010 (2012/5/3 12:13:34)

when you say inference normally wou;d not show up in the passage,  you mean inference would not show up in the assumption problem or  in  all the CR problem?

sdcar2010

Inference, by definition, is something you can derive from the passage.  Therefore, it SHOULD not show up in the passage.  This has nothing to do with question types.  It's a general rule in CR.

PhoebeQi

thank u sooooo much！

athenawujj

23. On a certain day, nine scheduled flights on Swift Airlines were canceled. Ordinarily, a cancellation is due to mechanical problems with the airplane scheduled for a certain flight. However, since it is unlikely that Swift would have the mechanical problems with more than one or two scheduled flights on a single day(Premise), some of the nine cancellations were probably due to something else. (Conclusion)
The argument depends on which one of the following assumptions?（Necessary Assumption）
Ordinarily mechanical problems just for few flight→Swift airlines canceled nine flight, there is another reason.
A.    More than one or two airplanes were scheduled for the nine canceled flights.
B.    Swift Airlines has fewer mechanical problems than do other airlines of the same size.
C.    Each of the canceled flights would have been longer than the average flight on Swift Airlines.
D.    Swift Airlines had never before canceled more than one or two scheduled flights on a single day.
E.    All of the airplanes scheduled for the canceled flights are based at the same airport.

Dear SDCQR;i don't understand why choose A?

sdcar2010

Necessary assumption. Use negation.

If you negate A), you have:
No more than one or two airplanes were scheduled for the nine canceled flights. Basically one or two airplanes were used for all nine flights.
If so, and if that one or two airplances had mechanical problem, all nine flights would have been delayed due to this reason. Thus the conclusion that it is something other than mechanical failure that caused the delay is wrong.

athenawujj

SDCAR，Hello,I got stuck.
When i do the CR,i cannot do it quickly.I don't know what  i should do to improve the speed.
Here is my plan.CAN YOU GIVE ME SOME IDEAS?
1.After reading your series, I redo OG.
2.Because i have the test next month, i want to go straight to the GWD?
is it ok??

sdcar2010

Everyone is different.  The speed when doing CR hinges on both your reading speed and your analytical speed. I do not know which one is "speed bump" here. If the former is the problem, you need to practice more on reading comprehension, if the latter, you need to practice recognizing argument structure. As I said again and again, if you find the main conclusion of the argument, you are half way to victory. Good luck.