Roland: The alarming fact is that 90 percent of the people in this

Question

Roland: The alarming fact is that 90 percent of the people in this country now report that they know someone who is unemployed.

Sharon: But a normal, moderate level of unemployment is 5 percent, with 1 out of 20 workers unemployed. So at any given time if a person knows approximately 50 workers, 1 or more will very likely be unemployed.

Sharon's argument relies on the assumption that

(A) normal levels of unemployment are rarely exceeded

(B) unemployment is not normally concentrated in geographically isolated segments of the population

(C) the number of people who each know someone who is unemployed is always higher than 90% of the population

(D) Roland is not consciously distorting the statistics he presents

(E) knowledge that a personal acquaintance is unemployed generates more fear of losing one's job than does knowledge of unemployment statistics

Argument Construction

Situation 
Roland is alarmed that 90 percent of the population knows someone who is out of work. Sharon replies that a normal level of unemployment is 5 percent, illustrating her point by saying that if a person knows 50 workers, at least one of them is likely to be unemployed.

Reasoning 
 What assumption does Sharon make in putting together her argument?  Sharon makes a general statement claiming that if a person knows 50 workers, it is likely that at least one of them is unemployed. Sharon’s generalization would not likely be true if unemployment were concentrated in certain geographically isolated areas.

(A) Sharon’s argument is about a normal level of unemployment; how rarely or frequently that level is exceeded is outside the scope of her argument.

(B) Correct . This statement properly identifies an assumption that underlies Sharon’s argument.

(C) Although Sharon’s argument is compatible with saying that even more than 90 percent of the population knows someone who is unemployed, nothing suggests that she assumes that this is true.

(D) Sharon’s argument is not based on the figure Roland cites and does not assume its accuracy or inaccuracy; her argument merely points out that his figure is not inconsistent with a normal rate 
of unemployment.

(E) The fear of losing a job is not part of Sharon’s argument; this statement is irrelevant.

The correct answer is B .

"Roland" Conclusion Question

Paul · Accepted Answer

B it is
A) This is not an assumption and will not affect the argument/conclusion given. 
B) negate this one and you get: 
unemployment  is  normally concentrated in geographically isolated segments of the population
What is the implication of the above? If unemployment is concentrated in certain areas, how can we say that if someone who knows 50 persons will very likely know more than 1 person who is unemployed? 
Let's take a simple number example. Country A has two cities: X and Y
City X: population = 100 --> 10 are unemployed
City Y: population = 100 --> 0 are unemployed
Total unemployment rate for country A: 10/200 = 5% --> as claimed by Sharon
As you can see in my example, unemployment is  concentrated in a geographical location : city X
Hence, if that someone who Sharon is talking about lives in city Y, is it right to say that that person is likely to know more than one person who is unemployed? No, because that person lives in a city where there is no unemployment whatsoever.
 Conclusion : We  need  to assume that unemployment  is not  isolated in geographically isolated segments of the population. If not, the argument falls apart.

GMATNinja · Answer

The heart of Sharon's argument is pretty straightforward: she thinks that what Roland sees is somewhat "normal", and not "alarming".

Let’s break down the reasoning behind her argument:

1. A "normal" unemployment rate is 1/20.
2. So if you know 20 typical workers, odds are good that one will be unemployed.
3. And then if you know 50 workers,  at least  1 of them will probably be unemployed.
4. Therefore, it’s likely at any given time that 90% of people in the country know at least 1 unemployed person.

In her reasoning, Sharon refers to nationwide levels of unemployment. When she jumps to step 4 of her argument, she assumes that the employment patterns of the 50 workers each of us knows personally will resemble the nationwide employment patterns. In order to accept this assumption, we need evidence that the normal unemployment rate in any given area will roughly match the normal rate of unemployment for the entire country. Otherwise, it could be the case that the unemployed workers are overwhelmingly concentrated in a few parts of the country, and most people elsewhere might NOT know any unemployed workers.

So Sharon's argument relies on which of these assumptions?

It makes no difference whether normal levels of unemployment are exceeded rarely or frequently. As long as the  current  level of unemployment is normal, then Sharon’s argument is valid.

In other words, normal levels of unemployment could be exceeded frequently. But according to Sharon, the data cited by Roland is evidence that unemployment levels are normal  right now . Sharon’s argument does not rely on choice (A), so eliminate this one.

Choice (B) gets to the heart of Sharon’s assumption. If unemployment is evenly distributed across the population as opposed to being concentrated in certain states, cities and industries, then we’ll have an easier time agreeing with Sharon. If (B) is true, then any person who knows approximately 50 workers -- anywhere in the country -- is likely to know at least one unemployed worker, even if unemployment levels are moderate.

If (B) were NOT true and unemployment levels were moderate, then we would expect people in the geographically isolated segments to know  several  unemployed workers. In that case, most people in  other  parts of the country would NOT likely know at least one unemployed worker. If (B) were not true, then Roland’s evidence would be "alarming", and Sharon’s argument would fall apart.

Let’s keep choice (B) for now and try to eliminate the rest.

Choice (C) could certainly weaken Roland’s argument (by suggesting that the evidence is normal, not alarming). But does Sharon’s argument  rely  on this assumption? What if unemployment levels are sometimes LESS than moderate? In that case, there would certainly be times when the number of people who each know someone who is unemployed is NOT higher than 90% of the population.

Regardless, we are only interested in the fact that that 90 percent NOW report that they know someone who is unemployed. According to Sharon, this is no cause for alarm. Sharon’s argument would be the same regardless of whether (C) is true, so we can eliminate this one.

Sharon’s argument doesn’t depend on whether Roland is honest. There would be no reason for continuing to this conversation if Roland were rattling off fake news he saw on Facebook, but Sharon’s logical connection wouldn’t be affected.

Sharon’s argument is basically, “Even  if  your evidence is true, there is no cause for alarm.” If the evidence is false, Roland might be a liar, but Sharon’s logic remains sound.

(D) isn't necessary, so we can eliminate it.

Choice (E) very well may be true, but it tells us nothing that would affect the logical argument Sharon is making. She says we shouldn’t be alarmed because normal unemployment rates explain the seemingly abnormal rates of knowing an unemployed person. Fear of losing one's job is completely irrelevant to her argument.

So (E) is out, and (B) is our answer.

mikemcgarry · Answer

Roland is concerned --- 90% of people in the country know someone who is unemployed, and Roland apparently takes this as evidence that unemployment is high. This is a somewhat bogus argument. Sharon raises what is at root a very sensible objection --- because 90% know someone who is unemployed does not necessarily mean the unemployment rate is high. I'm going to guess that the vast majority of the population, almost everyone, personally knows someone over the age of 80 --- this doesn't mean that the majority of the population is over 80, but just that there are enough 80+ year olds distributed in the population densely enough that virtually everyone knows at least one person like this. Sharon's argument is essentially a probabilistic argument --- if every person knows 50 people, then if 5% = 0.05 = 1/20 of all people are unemployed, then there's a very high chance that of the 50 random folks one person knows, at least one of them is unemployed. One subtle thing about this argument --- this argument works well if 1/20 is a true probability, that is, if we can pick essentially any group of fifty people, and the probability that any one person is unemployed is 1/20, and this probability is more or less constant as we look at different groups of 50. If the probability is not fixed --- if it's higher in some places and lower in other places --- then that changes the nature of the argument. Suppose, for simplicity, the entire country consists of just ten cities, with small and equal populations. Suppose people know each other well within each city, but essentially no one from one city knows any one from any other city. (This is a highly unrealistic scenario, just to demonstrate the logic.) SCENARIO #1 : 5% of the people in each of the cities are unemployed --- then, most people in each city would know someone unemployed. Because there's an even distribution, about 90% or more of the population would know someone unemployed, even though only 5% of the population is unemployed. This assumes more or less even distribution of the unemployed. This is consistent with Sharon's argument. SCENARIO #2 : Now, consider an extreme of population concentration --- 50% of the people in City #1 are unemployed, and everyone in the other nine cities are fully employed. Here, everyone in City #1 would know someone unemployed, but City #1 is only 10% of the population. Assume the folks in different cities don't know each other, so no one else know the unemployed in City #1. Thus, 5% of the population is unemployed, and only 10% of the population knows someone unemployed. In other words, if the unemployed are more-or-less evenly distributed in the population, that is, if we could go anywhere, any region or any subgroup of the population, and the probability that any single person is unemployed is about 5%, then we could have only 5% unemployment but a very high percentages, maybe 90%, who know someone who is unemployed: again, this is essentially Sharon's argument. BUT, if the unemployed are not even distributed, and are instead concentrated geographically in particular places, then Sharon's argument would no longer be valid. That's why (B) is an excellent answer, the best answer for this question. Does this make sense? Mike

crackgmat3 · Answer

A.

I am getting this by process of elimination.

(B) unemployment is not normally concentrated in geographically isolated segments of the population  -- Geographical isolation is not discussed in the argument. 

(C) the number of people who each know someone who is unemployed is always higher than 90% of the population  -- General statement 

(D) Roland is not consciously distorting the statistics he presents 
 -- This is not the assumption 

(E) knowledge that a personal acquaintance is unemployed generates more fear of losing one's job than does knowledge of unemployment statistics  -- General statement

haas_mba07 · Answer

Still not sure what the core point is? Can someone elaborate?

gmatmba · Answer

Roland is freakin out that 90% of the people in Xanadu know someone in that country who is unemployed. Sharon is asking Roland to chill out because that stat presented by Roland means that normal, moderate level of unemployment is 5 percent, with 1 out of 20 workers unemployed . So, if a resident of Xanadu knows 20 people, 1 of them will most likely be unemployed. Now this is only possible if the unemployed people are scattered evenly across the country. Thats what I made out of it

IanStewart · Answer

It should be B. Imagine you have the following situation:

a town of 50,000 has 100% unemployment, and no one in this town speaks to anyone else in the country
the other 950,000 people in the country, or 95% of the population, all have jobs

Then only 5% of your population would know anyone who was unemployed - the 5% in the isolated town full of unemployed people. Sharon's argument assumes that unemployment is spread fairly equally across the population.

PiyuMu · Answer

Hi,

Roland: The alarming fact is that 90 percent of the people in this country now report that they know someone who is unemployed.
Sharon: But a normal, moderate level of unemployment is 5 percent, with one out of 20 workers unemployed. So at any given time if a person knows approximately 50 workers, one or more will very likely be unemployed.

Sharon's argument relies on the assumption that
(A) normal levels of unemployment are rarely exceeded
(B) unemployment is not normally concentrated in geographically isolated segments of the population
(C) the number of people who each know someone who is unemployed is always higher than 90 percent of
the population
(D) Roland is not consciously distorting the statistics he presents
(E) knowledge that a personal acquaintance is unemployed generates more fear of losing one's job than does
knowledge of unemployment statistics

Explanation: Roland: It is a fact that- 90% of people of the country know someone who is unemployed.
Sharon: contradicts Roland's statement and says that average level of the unemployment of the country is 5%, with 1/20 is unemployed.
Conclusion of Sharon: so if a person knows 50 workers then at least one will be unemployed.

Assumption: More known people --> More number of unemployed people

A. OFS- we are not stated about the increase or decrease of unemployment.
B. Unemployment is for the country population, not just about the geographically isolated segments of the population- correct
C. always hight- extreme words- wrong
D. We are ask about Sharon's conclusion not of Roland's statement.
E. OFS

B: New Information, support the conclusion
But I am not understanding how to negate it. Means if i negate it like this: unemployment is normally concentrated in geographically isolated segments of the population,
then how can we connect it with conclusion?

Regards,
Mugdha.

tk1tez7777 · Answer

Hi Mate,

In assumption questions negation technique is very useful and if you want to succeed in the assumption questions you should learn the assumption very well.
This is how the negation technique works.
All people will be going to football match……Negate it….you will get….Not all people will be going to football match. Now here not all means not all…there is a difference between not all and none.
Suppose there are 100 people then not all mean not all the 100 or may be 99 may be 98 or 95 or 10 but not all 100….but none means definitely 0.

So in the argument above as B is the correct answer. What does B says:
 unemployment is not normally concentrated in geographically isolated segments of the population 
If you negate this you will get….unemployment is  not  normally concentrated in geographically isolated segments of the population…..
now what does this negation means. If all the unemployed people are concentrated in one town or one patch of the area then sharon's argument will shatter. How? Well this is how….If all the unemployed people are concentrated only in city A and in city B there are No unemployed people then in city B if a person knows approximately 50 workers, one or more will  not  very likely be unemployed. So people in city A will know someone one or more people who are unemployed but in city B it won't be true. So sharon is assuming that people are distributed randomly and are not concentrated in one area.

Let me know if this makes sense.

Ekland · Answer

GMAT is about pattern recognition.
The argument relies on statistics presented by two opponents.
Roland said something is Alarming.
Sharon's argument is:  Hei Roland that's not really alarming. 
Both guys based their opinions on statistical facts.

Whenever you see arguments based on statistics facts, as u already know, the validity of the conclusion is weakened if it is shown that the statistics is spurious or dubious. 
Lack of Structural Stability of data or statistics makes a statistical result unreliable. I.e if the average doesn't closely show what's happening in MOST data points, the result is unreliable. In another language, a data that skews badly off its mean will make the mean result unreliable. e.g if the average of a set of numbers is 5, that average will be more reliable if the numbers are (3, 4, 5, 6, 7) or (4,4,5,6,6) than if the numbers are (0, 0, 0, 12, 13) or (1, 1, 2, 10, 11).
each has average of 5.

Assume the numbers above represent unemployment rates in 5 cities)
In the two later sets the high or alarming numbers are concentrated at some cities.
Even though all sets show that the national unemployment rate is 5 which is Normal, It is alarming in some places.

Some macroeconomic indicators rely on arthmetic average.
But the trouble with arithmetic averages is already known.
It doesn't show you what's happening in the whole country.

Option B therefore defends Sharon's point from a most potent weakener: unreliable statistics, Abnormally distributed data. etc

Always bear in mind that CR questions involving data or statistics will test simple knowledge of validity of statistics anytime.

balaji4799 · Answer

Why isn't option A right. Isn't Sharon assuming that Option A (normal levels of unemployment are rarely raised).

Also, I didn't get the relation between one in 20 and one in 50 people. How are these two related? Though It is slightly clearer on how Sharon assuming option B to make that statement, Option A could also be true.

please explain

sayantanc2k · Answer

I found the following excerpt while going through my preparation notes:

correct B: negate this one and you get: 
unemployment is normally concentrated in geographically isolated segments of the population
What is the implication of the above? If unemployment is concentrated in certain areas, how can we say that if someone who knows 50 persons will very likely know more than 1 person who is unemployed? 
Let's take a simple number example. Country A has two cities: X and Y
City X: population = 100 --> 10 are unemployed
City Y: population = 100 --> 0 are unemployed
Total unemployment rate for country A: 10/200 = 5% --> as claimed by Sharon
As you can see in my example, unemployment is concentrated in a geographical location: city X
Hence, if that someone who Sharon is talking about lives in city Y, is it right to say that that person is likely to know more than one person who is unemployed? No, because that person lives in a city where there is no unemployment whatsoever.
Conclusion: We need to assume that unemployment is not isolated in geographically isolated segments of the population. If not, the argument falls apart.

As for A: Sharon just states the normal level of unemployment. There is nothing in her statement that indicates that she assumes that the normal levels are exceeded (or they don't).

aceGMAT21 · Answer

Roland:  The alarming fact is that 90 percent of the people in this country now report that they know someone who is unemployed.

Sharon:  But a normal, moderate level of unemployment is 5 percent, with 1 out of 20 workers unemployed. So at any given time if a person knows approximately 50 workers, 1 or more will very likely be unemployed.

Sharon's argument relies on the assumption that

(A) normal levels of unemployment are rarely exceeded
(B) unemployment is not normally concentrated in geographically isolated segments of the population
(C) the number of people who each know someone who is unemployed is always higher than 90% of the population
(D) Roland is not consciously distorting the statistics he presents
(E) knowledge that a personal acquaintance is unemployed generates more fear of losing one's job than does knowledge of unemployment statistics

My take -

First lets identify the conclusion for this question. Question asks to find the  assumption of Sharon's argument .

Conclusion -  At any given time if a person knows approximately 50 workers, 1 or more will very likely be unemployed.
or At any given time if a person knows approximately 50 workers,  at least one  will very likely be unemployed.

Any of the options which support the negation of the above argument, that is will actually break the above argument. Will be the answer. 
 Negation of Conclusion -  At any given time if a person knows approximately 50 workers,  none  will very likely be unemployed.

(B) Negated - unemployment is normally concentrated in geographically isolated segments of the population.
It supports the negation of conclusion above. At any given time if a person knows approximately 50 workers,  none  will very likely be unemployed. Because all the unemployed people are normally concentrated on a geographically isolated segments of the population. So, no one knows of these geographically isolated unemployed people. Thus, B is the correct answer.

The image attached clears the option B in more detail. Please let me know, if someone has still any doubt on this question.

radhikakhemka007 · Answer

What should be the approach to the question? 
the options are really ambiguous for me to understand.
Please explain in detail.

GMATNinja · Answer

According to Sharon, the fact that 90 percent of the people in this country now report that they know someone who is unemployed is no cause for alarm. Why not? .. because if the average person knows about 50 workers and if the moderate unemployment level is 5%, then it is likely that the average person will know at least one unemployed person. In other words, the fact that 90 percent of people know someone who is unemployed  might  be explained by  moderate  unemployment, not necessarily by  alarming  levels of unemployment.

We need an answer choice on which that line of reasoning depends.

Say we have moderate levels of employment (with 1 out of 20 workers unemployed). If unemployment is spread out evenly across the country, then the author's argument makes sense. In other words, if unemployment is evenly spread, then I can pick any 100 workers and expect to find about 5 unemployed workers in that group.

What if most of those unemployed workers are concentrated in a few geographically isolated segments of the population? In that case, if unemployment is moderate, we would expect MOST people to NOT know an unemployed worker and SOME people to know several unemployed workers.

But Roland tells us that now 90 percent of the people in this country report knowing someone who is unemployed. If unemployment is concentrated in only a few isolated segments, then this statistic is alarming. Why?... because now most people, even those who are NOT in those isolated segments, know someone who is unemployed. Unless unemployment is evenly spread, Roland's statistic suggests that unemployment is much higher than 5%.

I hope that helps!

OC2910 · Answer

Roland: The alarming fact is that 90 percent of the people in this country now report that they know someone who is unemployed.

Sharon: But a normal, moderate level of unemployment is 5 percent, with 1 out of 20 workers unemployed. So at any given time if a person knows approximately 50 workers, 1 or more will very likely be unemployed.

Sharon's argument relies on the assumption that

assumption question
BID : sharon states a data :1/20 or 5% employment in the overall region stating the 90 percent data is not so high
Missing GAP :the Data is sufficient to counter roland's argument
 :numbers and percentages coincide

so now looking at options

(A) normal levels of unemployment are rarely exceeded ( Not an assumption rather the conclusion)

(B) unemployment is not normally concentrated in geographically isolated segments of the population  ( hold - increases the applicability of the data point 
for example: if the unemployment rate of 1/20 is not applicable to other locations then sharon cannot contradict Roland argument )
 
(C) the number of people who each know someone who is unemployed is always higher than 90% of the population  (no mention of the same )
 
(D) Roland is not consciously distorting the statistics he presents  (we have no idea : out of scope )

(E) knowledge that a personal acquaintance is unemployed generates more fear of losing one's job than does knowledge of unemployment statistics (out of scope )

correct B

Mehemmed · Answer

Dear  GMATNinja ,

Initially, I selected C as the answer. After reading your explanation above I understood that there can be periods where unemployment rate is more or less than 5%. Also, the word "always" should have grabbed my attention.
However, I still don't understand B. How can we infer that Sharon assumed geographical distributions of workers, and Roland says  The alarming fact is that 90 percent of the people  in this country  now report that they know someone who is unemployed . Doesn't he assume the whole country in his argument?

GMATNinja · Answer

Yes, Roland is referring to the entire country (90 percent of the people in this country now report that they know someone who is unemployed).

Forget about Roland for a second and think about normal unemployment (5%--i.e. 1 in 20 workers are unemployed). Now let's imagine that unemployment is spread evenly across the country. In that case, if you know 20 workers, there's a good chance that you know an unemployed person (since, on average, 1 in 20 are unemployed). And if you know 50 workers, 1 or more will very likely be unemployed. This is Sharon's argument.

But that argument ONLY works if we assume that unemployment is spread evenly across the country... why? Consider a country with 1 million workers and normal unemployment (so 50,000 unemployed workers). What if ALL 50,000 of those unemployed workers live in the same city? In that case, everyone who lives in that city will likely know someone who is unemployed, but everyone else in the country will NOT know someone who is unemployed.

That is obviously an extreme example. The point is that if unemployment is concentrated in a few isolated areas, then people OUTSIDE of those areas will be  less  likely to know someone who is unemployed. If unemployment is at 5% and distributed evenly, then anyone who knows 50 workers will likely know an unemployed worker (Sharon's argument). If unemployment is at 5% and NOT distributed evenly, then only the people in the high-concentrations areas will likely know someone who is unemployed. Outside of those areas, people who know 50 workers are MUCH LESS likely to know an unemployed person.

So if unemployment is evenly spread and 90% of people in the country know someone who is unemployed, then the data can be explained by normal unemployment figures. However, if unemployment is concentrated and, still, 90% know someone who is unemployed, then unemployment is likely higher than normal.

I hope that helps!

testprep11 · Answer

Hi  GMATNinja  ,

Thanks for this detailed explanation.

I have a general and a specific doubt related to this question.

Specific Doubt -  
As per me , Sharon is making 2 assumptions at two different stages of her reply.
1 - She assumes that what ever she is going to reply will contradict/explain what Roland has said, i.e. 90% people of the country know someone unemployed
2 - In her reply itself, she assumes that , as lucidly explained by you, the unemployment is not geographically concentrated.

My problem was that I concentrated on the 1st assumption(if it can qualify as an assumption of Sharon) that 90% can be explained by the 1/20 logic . And if an answer choice says that , well, not every time it is 1/20 then it simply damages that assumption.

General Doubt -  
In cases like the current question. Where there Is 1st person and the 2nd person replies to the 1st by giving a statement which - 
a) Is making an assumption that the reply as a whole addresses the problem.
AND 
b) The reply content itself is assuming something.

Then in such a case which assumption to target. first one or the second one?

I hope I am able to express my line of thought.

Thanks

Roland: The alarming fact is that 90 percent of the people in this

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Critical Reasoning (CR) Questions

Roland: The alarming fact is that 90 percent of the people in this

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards