an old CR

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an old CR

by diebeatsthegmat » Mon Oct 04, 2010 12:32 pm
what is your answer and explanation for this CR?

Left-handed persons have an advantage over right-handed persons on tasks that are controlled by the right hemisphere of the brain and painting, for most people, is a task mostly governed by the right hemisphere of the brain. However, left-handed persons contract viruses, such as influenza, more frequently than do right-handed persons.

The information above, if true, best supports which of the following hypotheses?


(A) There is a greater proportion of left-handed persons among painters than there is among non-painters.
(B) Most people who contract influenza or other viruses are left-handed rather than right-handed.
(C) If a left-handed person contracts a virus similar to influenza, that person will probably be a painter.
(D) Most left-handed painters are more susceptible to influenza than is the population as a whole.
(E) There are a greater proportion of left-handed persons among painters than there are right-handed persons among non-painters.

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by slash » Mon Oct 04, 2010 8:17 pm
My pick is D

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by psychomath » Mon Oct 04, 2010 8:21 pm
I will go with D
"However, left-handed persons contract viruses, such as influenza, more frequently than do right-handed persons. "
This particular part in the question made me choose D over the other choices-which were either extreme or didn't make much sense!

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by samudranb » Mon Oct 04, 2010 10:37 pm
Even I feel the answer option D is right.

But I was not able to satisfactorily eliminate A. Can anybody explain clearly why A is wrong?

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by pzazz12 » Tue Oct 05, 2010 3:49 am
I think answer is D.

what is OA?

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by mj78ind » Tue Oct 05, 2010 5:32 am
samudranb wrote:Even I feel the answer option D is right.

But I was not able to satisfactorily eliminate A. Can anybody explain clearly why A is wrong?
I go with D. A is out because the sentence says they are good at painting that does not mean a majority who are good at painting actually become painters.

D is clear of the population, there are painters the left handed will be more susceptible than the normal population (which comprises right handed people who are less susceptible)

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by bubbliiiiiiii » Wed Oct 06, 2010 4:48 am
My pick is D.

Why not A?
Stimulus refers to advantage rather than proportion that left handed painters have over right handed painters whereas the option A refers to the proportion part. Nothing can be concluded on the number of LHP over RHP from the stimulus. Thus not appropriate.

Hope it helps!

OA please!

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by pnk » Wed Oct 06, 2010 10:20 am
Left-handed persons have an advantage over right-handed persons on tasks that are controlled by the right hemisphere of the brain and painting, for most people, is a task mostly governed by the right hemisphere of the brain. However, left-handed persons contract viruses, such as influenza, more frequently than do right-handed persons.

(A) There is a greater proportion of left-handed persons among painters than there is among non-painters.
False - Left-handed persons have advantage over right-handed persons on tasks that require the use of right-hemisphere. Paiting is a right hemisphere activity. It means, left-handed persons have advatage in painting over right-handed persons. This just talks about advantage....no indication of proportion. Additionally it means if one right-handed and one left-handed person is painting...it is likely that left-handed person will make a better painting.

(D) Most left-handed painters are more susceptible to influenza than is the population as a whole.
False. We do not have any information about population as a whole. We only know left-handed catch influenza more frequently than right-handed. But we do not have any information about left-handed person with respect to ambidexterous persons.

(C) If a left-handed person contracts a virus similar to influenza, that person will probably be a painter. True : left-handed person is right-hemisphered; influenza affects left-handed more; printers are left-handed. Therefore it is possible (mark the word 'probably' in the option). I pick C

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by ankurmit » Thu Oct 07, 2010 8:08 pm
I will pick C
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by Testluv » Thu Oct 07, 2010 10:03 pm
In those inference questions that use the word "support" we should think about authorial intent and what conclusion the passage was designed to support.

Most often, the right answer to these questions is simply the main point, which the passage will clearly imply but not outright say.

The hypothesis best supported is choice D. If choice D were false, then the last sentence of the passage pretty much also becomes false (denial test). Thus, choice D is a supportable inference. Left-handers get the flu more often than do right-handers. Since the population is made up of left-handers as well as right-handers, the population as a whole would get the flu less often than just the left-handers, which is the segment of the population that gets the flu more often. Although pnk is right to bring up the fact that choice D doesn't talk about ambidextrous individuals that would be a technical point which would be far more important had the question said "if the statements above are true, which of the following MUST BE TRUE?" Here, the passage BEST SUPPORTS the hypothesis in choice D.

Choice A is a distortion. Just because left-handers would make for better painters doesn't mean more of them actually become painters. Also, even if we ignored that problem, in order to deem choice A correct, we would have to assume that the population is made up of equal parts left-handers and right-handers. In fact, this last reason is why choices B and E are incorrect.

Choice C commits the same distortion as does choice A. Again, having an advantage in painting doesn't mean you're more likely to become a painter. Further, choice C presumes a causal relationship when in fact we only have a 3 part correlation: left-handedness--having an advantage in painting--get the flu more often. As we all know, we can't infer causality from a mere correlation.
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by pradeepkaushal9518 » Fri Oct 08, 2010 12:29 am
yes D is supporting

what happen to ankur mittal

ankur is the only guy in the forum who gives one line answer
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by Testluv » Fri Oct 08, 2010 1:15 am
pradeepkaushal9518 wrote:yes D is supporting
I don't mean to be nitpicky Pradeep but I'm going to use your response as the starting point for relating some specifical tactical advice for the CR section. Anyone that wants to skip the theory can scroll down to the TAKEAWAY at the bottom of this post.

D is not supporting. Instead, it's supported.

Why should we care?

Because this is what lies at the crux of a common question-type identification pitfall: mixing up strengthen and inference questions.

These two question types often get mixed up because much of the language in each of the question stems is similar: words like "true", "support", etc frequently show up in both stems. And treating an inference question as strengthen or vice-verse means one will also likely apply the wrong approach. Further, the test-maker is aware of this, and will, accordingly, design some wrong answers to trap people who fall into this pitfall.

So, how do we not make this mistake? That is, once we know it is a strengthen or inferece question, what's the fastest and simplest way to determine which one it is?

Read the question stem. If it reads:

"which of the following, if true, most strengthens the argument above?"

then what are you told to treat as true? You are told to treat the "following" as true. What follows the question stem? Why, the answer choices of course. So, here we are treating the answer choices below--and not the statements above--as true. And what is the direction of support? From the stimulus to the answer choices or from the answer choices to the stimulus? It's from the answer choices to the stimulus: the question stem read: "...argument above?" (Imagine an arrow whose tail is at the answer choices and whose head is at the stimulus). This is a strengthen question.


What about this question stem:

"If the statements above are true, which of the following is most strongly supported?"
or
"Which of the following is most strongly supported by the statements above?"

What are you treating as true and what is the direction of support? You are told to treat the statements above--not the answer choices below--as true, and the direction of support is from the stimulus above to the answer choices below (imagine an arrow whose tail is at the stimulus and whose head is at the answer choices). This is an inference question.

TAKEAWAY: we can tell if it is a strengthen vs inference question by asking "what is the direction of support?" If it is from up-to-down, it is an inference question. If it is from down-to-up, it is a strengthen question.
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by pradeepkaushal9518 » Fri Oct 08, 2010 5:21 am
thanks test luv for giving time for my reply
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by pnk » Tue Oct 12, 2010 12:20 pm
Testluv wrote:In those inference questions that use the word "support" we should think about authorial intent and what conclusion the passage was designed to support.

Although pnk is right to bring up the fact that choice D doesn't talk about ambidextrous individuals that would be a technical point which would be far more important had the question said "if the statements above are true, which of the following MUST BE TRUE?" Here, the passage BEST SUPPORTS the hypothesis in choice D.
Hi Testluv,

I felt both Must be True and best supports are inference questions - from ARGUMENT TO ANSWER CHOICES. Could you explain between them more pls.

Is the undertanding that 'best supports' hypothesis questions can have information not mentioned in the argument - correct! Pls help

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by Derek1988 » Fri Jan 07, 2011 9:49 am
why B is wrong?