Knewton CR 1

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Knewton CR 1

by reply2spg » Thu Apr 01, 2010 10:43 am
Many remote hiking trails do not have directional markers. Such markers would make it easier for hikers to navigate and exit these trails, particularly when weather conditions are poor, and would therefore seem be an aid to hiker safety. However, after Greenfield State Park placed directional markers on all of its remote hiking trails, the number of hikers who became lost for dangerously long periods of time in this park increased by 30 percent annually.

Which of the following, if true, most helps to explain the increase in the number of hikers becoming lost for dangerous amounts of time?

(A) Greenfield State Park has an unusually large number of remote hiking trails.
(B) It can be as difficult for hikers to determine their location at night as it is when weather conditions are poor.
(C) Prior to the installation of the directional markers, more hikers became lost on Greenfield State Park's remote hiking trails than on most other state parks' remote hiking trails.
(D) Many hikers become lost on remote hiking trails because of disorientation due to dehydration rather than because of insufficient directional markers.
(E) After the directional markers were placed on the trails, many hikers who had specifically avoided hiking on remote trails no longer did so.

OA E though I got it correct I am confused between D and E. [spoiler]What is the best reason to eliminate D? Since we have to assume extra premise in both D and E, then why not D?[/spoiler]
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by outreach » Thu Apr 01, 2010 11:22 am
(D) Many hikers become lost on remote hiking trails because of disorientation due to dehydration rather than because of insufficient directional markers.
D does not show a relationship on how number of hikers who became lost for dangerously long periods increased after markers were placed
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by subgeeth » Thu Apr 01, 2010 11:25 am
Why B is incorrect?

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by gmatmachoman » Thu Apr 01, 2010 11:26 am
reply2spg wrote:Many remote hiking trails do not have directional markers. Such markers would make it easier for hikers to navigate and exit these trails, particularly when weather conditions are poor, and would therefore seem be an aid to hiker safety. However, after Greenfield State Park placed directional markers on all of its remote hiking trails, the number of hikers who became lost for dangerously long periods of time in this park increased by 30 percent annually.

Which of the following, if true, most helps to explain the increase in the number of hikers becoming lost for dangerous amounts of time?

(A) Greenfield State Park has an unusually large number of remote hiking trails.
(B) It can be as difficult for hikers to determine their location at night as it is when weather conditions are poor.
(C) Prior to the installation of the directional markers, more hikers became lost on Greenfield State Park's remote hiking trails than on most other state parks' remote hiking trails.
(D) Many hikers become lost on remote hiking trails because of disorientation due to dehydration rather than because of insufficient directional markers.
(E) After the directional markers were placed on the trails, many hikers who had specifically avoided hiking on remote trails no longer did so.

OA E though I got it correct I am confused between D and E. [spoiler]What is the best reason to eliminate D? Since we have to assume extra premise in both D and E, then why not D?[/spoiler]
D is a red Herring!!Basically its a Out Of Scope Option.I used to call it as "boobytrap".Why so??The stem clearly introduces a paradox based on introduction of directional markers.But D introduces a alternate reason, thereby by not nailing the paradox. Dont get carried away by those boobytraps.Its oneway of distracting a advanced test taker.

Coming to E, How does it resolve the paradox.??
We shall take some numbers to visualise the scenario.
Let us assume 10,000 people are living in Greenfield State Park.

Before Introduction of "directional hikers", let us assume only 1000 people took part in hiking. And out of them, 10% were lost becox of insufficient directional markers. that mounts to 100 people.

Now after introduction of directional Markers, according to E, more people have participated in Hiking. Let us assume 1300 people have participated in Hiking. And again only 10 % has lost their direction. That amounts to 130 people.

Just going by thru the figures(130 & 100) we may come to conclusion that 30% lost rate has increased. But it's actually NOT. Since the Total Number of people participated increased, the lost number (NOT the LOST percentage) has increased.
Still the lost percentage of people is 10 % only even after introduction of directional markers.

To get this above said scenario, E introduces the condition that More people have participated in Hiking.

D is Just a Red Herring!!

IMO, this kinda CR's comes at very high level!! Since Numbers/Percentages & that too in resolve the paradox is killer combination to set the candidate on fire!!

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by Testluv » Thu Apr 01, 2010 4:34 pm
This:
D does not show a relationship on how number of hikers who became lost for dangerously long periods increased after markers were placed
is a great explanation for why D is wrong.

In paradox questions, it is important to keep the paradox clear in mind while going through the answer choices. In other words: "what is the surprise and why is it surprising?" is the question you should have burning through your head. Then, go through the answer choices, searching for one that resolves the surprise.

The surprise is that more people got lost after the introduction of the markers even though the purpose of the markers is to guide hikers. D fails to explain why MORE people got lost after the introduction of the directional markers.

_____


Sometimes, we can also make a prediction in this question type. When I was reading this question, I thought that the right answer might be something about hikers OVER-relying on the markers, and thus becoming lost. Choice E basically matches this prediction. A word of warning though: don't become over-attached to the prediction in paradox questions: there may be multiple ways the paradox can be resolved.

If we are good with numbers, and with picking numbers, we COULD also analyze this quantitatively as gmatmachoman has.
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by reply2spg » Mon Apr 05, 2010 5:45 pm
Thanked to machoman and testluv. It is nice explaination. Testluv, what would be the range of this question?

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by gmatmachoman » Mon Apr 05, 2010 9:47 pm
reply2spg wrote:Thanked to machoman and testluv. It is nice explaination. Testluv, what would be the range of this question?
Bro,
It certainly should come in high 700's. As i Said in my previous post, Its a kiler combination of Numbers/percentage/Pardox.

GMAC cant have better combination than this one!!

Probably TestLuv can throw the range!

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by kevincanspain » Tue Apr 06, 2010 12:23 am
This question is modelled after a GMATPrep question:

Many small roads do not have painted markings along their edges. Clear edge
markings would make it easier for drivers to see upcoming curves and to judge the
car's position on the road, particularly when visibility is poor, and would therefore seem
to be a useful contribution to road safety. However, after Greatwater County painted
edge markings on all its narrow, winding roads, the accident rate along those roads
actually increased slightly.

Which of the following, if true, most helps to explain the increase in the accident rate?

A. Greatwater County has an unusually high proportion of narrow, winding roads.
B. In bad weather it can be nearly as difficult for drivers to see the road as it is at
night.
C. Prior to the painting of the edge markings, Greatwater's narrow, winding roads
already had a somewhat higher accident rate than other Greatwater County
roads.
D. Many of the accidents on narrow, winding roads involve a single vehicle veering
off the road, rather than the collision of two vehicles.
E. After the markings were painted on the roads, many driver who had gone out
of their way to avoid driving on those roads at night no longer did so.
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by Phirozz » Tue Apr 06, 2010 1:05 am
kevincanspain wrote:This question is modelled after a GMATPrep question:

Many small roads do not have painted markings along their edges. Clear edge
markings would make it easier for drivers to see upcoming curves and to judge the
car's position on the road, particularly when visibility is poor, and would therefore seem
to be a useful contribution to road safety. However, after Greatwater County painted
edge markings on all its narrow, winding roads, the accident rate along those roads
actually increased slightly.

Which of the following, if true, most helps to explain the increase in the accident rate?

A. Greatwater County has an unusually high proportion of narrow, winding roads.
B. In bad weather it can be nearly as difficult for drivers to see the road as it is at
night.
C. Prior to the painting of the edge markings, Greatwater's narrow, winding roads
already had a somewhat higher accident rate than other Greatwater County
roads.
D. Many of the accidents on narrow, winding roads involve a single vehicle veering
off the road, rather than the collision of two vehicles.
E. After the markings were painted on the roads, many driver who had gone out
of their way to avoid driving on those roads at night no longer did so.
whats the answer for this question ?

Previous question talks about absolute value and perfectly framed and this one about accident rate.
A B C and D are out of scope. And E does not show why accident rate will increase.

If E is right, then we need to make two assumptions
1.Those drivers who were avoiding those roads at night are not good at driving
2. Even after road markings, these drivers are not going to show improvement in their driving.

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by gmatmachoman » Tue Apr 06, 2010 4:23 am
Phirozz wrote:
kevincanspain wrote:This question is modelled after a GMATPrep question:

Many small roads do not have painted markings along their edges. Clear edge
markings would make it easier for drivers to see upcoming curves and to judge the
car's position on the road, particularly when visibility is poor, and would therefore seem
to be a useful contribution to road safety. However, after Greatwater County painted
edge markings on all its narrow, winding roads, the accident rate along those roads
actually increased slightly.

Which of the following, if true, most helps to explain the increase in the accident rate?

A. Greatwater County has an unusually high proportion of narrow, winding roads.
B. In bad weather it can be nearly as difficult for drivers to see the road as it is at
night.
C. Prior to the painting of the edge markings, Greatwater's narrow, winding roads
already had a somewhat higher accident rate than other Greatwater County
roads.
D. Many of the accidents on narrow, winding roads involve a single vehicle veering
off the road, rather than the collision of two vehicles.
E. After the markings were painted on the roads, many driver who had gone out
of their way to avoid driving on those roads at night no longer did so.
whats the answer for this question ?

Previous question talks about absolute value and perfectly framed and this one about accident rate.
A B C and D are out of scope. And E does not show why accident rate will increase.

If E is right, then we need to make two assumptions
1.Those drivers who were avoiding those roads at night are not good at driving
2. Even after road markings, these drivers are not going to show improvement in their driving.
@kevincanspain:

Greta question.

@ Phiroz:
I have gone thru ur reading. Plz go thru mine or testluv explanation .It will certainly solve ur "preoccupied" doubts.

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by Phirozz » Tue Apr 06, 2010 4:41 am
@gmatmachoman

ur and testluv's explanation shows that there is absolute increase and not %age.
But in the new question rate is increased

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by Testluv » Tue Apr 06, 2010 6:05 am
Phirozz wrote:@gmatmachoman

ur and testluv's explanation shows that there is absolute increase and not %age.
But in the new question rate is increased
In the original question posted by reply2spg, the distinction between numbers and rate is neither here nor there because we don't have any reason to believe that there are more hikers than they're used to be. In other words, the total number of hikers hasn't changed but more of them are getting lost--or they are getting lost at a higher rate. If the total number of hikers has not changed, then there is both a greater number getting lost, and a greater fraction getting lost.
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by ssgmatter » Tue Apr 06, 2010 7:47 am
@Gmatmacmohan-->that was too insightful explanation for option D...Got some of my fundas clear here.....

@Testluv-->What to say....you just make it so simple and smooth that these CR's seems like a cakewalk...

Cheers!
Best-
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by gmatmachoman » Tue Apr 06, 2010 11:00 am
ssgmatter wrote:@Gmatmacmohan-->that was too insightful explanation for option D...Got some of my fundas clear here.....

@Testluv-->What to say....you just make it so simple and smooth that these CR's seems like a cakewalk...

Cheers!
Bhai,

In some of Our posts we have given Standing Ovation to TestLuv....May be u can check his begining 100 posts...Lovely & awesome...

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by Phirozz » Tue Apr 06, 2010 11:42 pm
Testluv wrote:
Phirozz wrote:@gmatmachoman

ur and testluv's explanation shows that there is absolute increase and not %age.
But in the new question rate is increased
In the original question posted by reply2spg, the distinction between numbers and rate is neither here nor there because we don't have any reason to believe that there are more hikers than they're used to be. In other words, the total number of hikers hasn't changed but more of them are getting lost--or they are getting lost at a higher rate. If the total number of hikers has not changed, then there is both a greater number getting lost, and a greater fraction getting lost.
got it...
thanx a ton testluv