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Question

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-Hong 


  Percentage Trap   

I would like to add Percentage Trap to this llist. It can be best explained with this example:

 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 3 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. 

Anand's explaination:
 Guys this is a beauty. Please hammer this into your head. This is a standard percentage trap. Let me elaborate.

Assume that last year 1000 people in the US moved out of state to retire. 
Of this say 10% moved to florida = 100 people 
So 90% moved to states other than florida right?

This year 20000 people moved to other state to retire 
Of this say 8% moved to florida = 160 people. 
So 92% moved to states other than florida right?

Though the %of people moving to florida has decreased ( because %of people moving to otherstates has increased ) number of people moving to florida has infact increased from 100 to 160. So the local businesses are gonna do great.

The bold portion is what (D) says and thus weakens the argument more seriously than (C).

Prema · Answer

You considered C as the close option. Can you explain whay not A?

thanks,
Prema

du_bill · Answer

If A says something like below, it could seriously weaken the argument. Otherwise, the negative effect may still be there...

A. Florida attracts more people who move from one state to another when they retire than does any other state   over past ten years  .

du_bill · Answer

to make it clear:
Florida attracts more people who move from one state to another when they retire than does any other state. The percentage of attraction grows over past ten years.

Prema · Answer

Well I was confused bet. A& D. But I guess D explains it better.

Thanks,
Prema

Taku · Answer

Like Prema, I thought (A) is the right answer, but see (D) is the best one. 

However, can somebody help me to better understand why A is not correct? Is A a wrong anser, or just not better than (D)? 

I see some explanation adding "over past ten years", but don't really find a reason to justify A is not correct. Thank you.

jpv · Answer

Principle:  something fundamental that we do not question. This would be somewhat stronger than a fact because it is not specific to a limited number of cases but instead, apply to a broader range of scenarios(and often deeper in meaning). For instance, you will not talk about the principle that crime is increasing in large cities. Instead, it is a fact which applies to large cities. However, you will talk about the principles of Physics or the fundamental principles of Human Rights. I believe principles convey a stronger connotation than mere facts. 

 Fact:  something taken as true at face value (stats, historical events) 

 Evidence:  what is used to support a conclusion (examples, stats, historical events). Although these may include facts, it is usually stronger than facts because they are direct elements needed for the conclusion to stand whereas facts are not necessary for the latter to stand 

 Pre-evidence:  This is a bit of a stretch. It will not often be on the test but it seems very similar to "background" information as described below. 

 Background:  Elements needed to put the evidence into context but which, as stand alone pieces of information, might not constitute what is called an evidence necessary to arrive at a conclusion. For instance, blood tests performed on one thousand persons may reveal that 35% of those persons were HIV infected. However, the background information could be that the test was performed in more underinformed regions of the world where AIDS knowledge is at a minimum. As you can see, the fact that the test was performed in more underinformed regions is not in and of itself an evidence because it does not allow us to come to a conclusion. Instead, the 35% stats, as a stand-alone piece of info, is what will lead us to the conclusion we want. However, the background info is also crucial and cannot be omitted; it is required background info. 

 Consideration:  Something which was taken into account or given some thought before arriving to the conclusion. 

 Premise:  This is usually a required statement to arrive at a conclusion. Evidence and facts want to prove something to you whereas premises are there to logically lead you to a conclusion. The best example of premises is the ones included in syllogisms. For instance, you can say that(premise1) when it rains, you go outside. Then, it rains(premise2). You have to be outside(conclusion). 

 Assumption:  Unstated information which will link the argument to a logical conclusion. Without this, the argument falls apart. 

 Conclusion:  Self-explanatory 

 Inference:  Something that might not be explicitly stated or proved. For instance, you may say that 95% of GMAT test-takers have over 340. We can reasonably infer that Anthony will get more than 340 on his GMAT based on the fact given. I think the main difference b/w an inference and a conclusion is that the former might not be the final line of an argument. For instance, there could be facts/evidence given, an inference in b/w, and then the conclusion. An inference can be an intermediate step before the conclusion which will sum up the whole passage. Also, a conclusion seems to be stronger because it is based on stronger facts/evidence. As in my previous example, we can reasonably infer that Anthony got 340+ on his GMAT but we cannot conclude that he got 340+. See the nuance?

Folaa3 · Answer

I can't seem to see a clear distinction between Inference and Assumption. Anyone care to shed some light? Thanks

saurya_s · Answer

So what are other traps? Hong Hu, since you are so good at them, perhaps you can add your picks.

inder oberoi · Answer

Hi there....
i jus read ur post over here and i have some doubts which if ne 1 cd please explain....the choice that u say reads as follows:

 The total number of people who retired and moved to another state for their retirement  has increased significantly over the past ten years. 

the first part of this sentence clearly says that the total no. of people moving to the other staes for retirement has increased and not the total no of people who retired!!

please explain whether this is a valid doubt coz i find option C to be a better and a noncontrovertial option!!

thanx....
inder oberoi

savvy · Answer

hi guys,

this my first post...

the distinction b/w inference and assumption is that assumption is always for conclusion....

HongHu · Answer

Assumption is something you need for you to draw your conclusion. Inference is a judgement that you draw from existing facts.

cybera · Answer

Nice post guys...I liked the example too..

Yes inference is the stage just before the conclusion, it may or may not correct. Say, there is a factor of 'doubt' attached with inference but not with conclusion

vishal.b21 · Answer

With all options available and applying POE as well, we land up as the least stinking one and that is D, I believe with the way explanation has been done, i find D as the possible choice, Anyways whats the OA?

thimmaiah · Answer

Real Good one JBV... Never looked at these Q from the % perspective before. Guess C would have been the right answer without considering the percentage angle.

Thanks

Thimmaiah.B.M

jksingh21 · Answer

In my opion C is not correct due to following reason:

C. There are far more local businesses in Florida that cater to tourists than there are local businesses that cater to retirees. 

This statement does not weaken or strengthen author's claim of impact on "local businesses in Florida cater to retirees" and hence not an option. 

Even though there are less businesses that cater to retirees (than tourists), it does not mean that they will not feel the impact if there were less ritirees settling in Florida. 

Correct me if I am wrong.


Cheers!

ATLiens073 · Answer

Answer is D

A is wrong because they are talking Florida has more number of people coming in than any other state.. this matter is irrelevant since we are talking about the percentage drop in the number of people coming to florida. Note, you can still have a percentage drop in population coming into florida and still have a greater number of people coming into Florida than any other state. So A does not weaken the argument as much as D.

workedupamigo · Answer

A and C cant be answers possibly for the below question :
Florida attracts more people who move from one state to another when they retire than does any other state.
The idea is not to compare florida with any other state, the conclusion deals with local businesses in florida depending on retirees in florida.

D.
A. 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 3 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.

C. There are far more local businesses in Florida that cater to tourists than there are local businesses that cater to retirees.
The above statement, assumes the business catering to tourists will offset the losses incurred by businesses catering to tourists, thats assuming the number of tourists atleast remains the same, or doesnt go below the current level. it is quite possible that the number of tourists does infact has reduced over the past ten years. We cant safely assume the pattern of number of tourists over the last ten years.

hence D makes the logical sense, based on POE.

Or was i totally hopeless there....??

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. :oops:

krishnosarkar · Answer

Moreover, in all the percentage problems, please notice that there can always be a chance of a flaw in terms of the "TOTAL NUMBER". Most of the percentage problems tests on that particular point.

What is your observation.

netcaesar · Answer

In my opinion, we have to be very cautios with this kind of questions.

In my opinion, at first sight the option A would be the right answer.

Nevertheless, if we think deeply in option D, it is the correct answer because of the explanation that is on the top of this post.

So we have to be very cautious reading the CR at first sight, because it is likely that we mistake the answer at first sight.

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