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MGMAT CR

by punitkaur » Fri Nov 06, 2009 6:09 pm
Antoine: The alarming fact is that among children aged 19 years and younger, the number taking antipsychotic medicines soared 73 percent in the last four years. That is greater than the increase in the number of adults taking antipsychotic medicines during the same period.

Lucy: But the use of antipsychotic drugs by adults is considered normal at the current rate of 11 adults per 1,000 taking the drugs. In contrast, the number of children on antipsychotic medication last year was 6.6 per 1,000 children.

Lucy's argument relies on the assumption that ______.

A)normal levels of antipsychotic drug use are rarely exceeded.

B)the percentage of adults taking antipsychotic medication is always higher than the percentage of children on such medication.

C)the use of antipsychotic medication in children is no different from the use of such medications in adults.

D)Antoine is not consciously distorting the statistics he presents.

E)a rapid increase in the number of children taking antipsychotic drugs generates more fear of random violence by adolescents than does knowledge of the absolute number of children on such medications.

OA is C. While I can't find anything wrong with the OA, my question is whats wrong with D?

Although Lucy is not directly using the statistics presented, she has to assume that they are accurate to counter argue. so for that she has to believe in Antoine which means D.

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Re: MGMAT CR

by Testluv » Fri Nov 06, 2009 8:55 pm
punitkaur wrote:Antoine: The alarming fact is that among children aged 19 years and younger, the number taking antipsychotic medicines soared 73 percent in the last four years. That is greater than the increase in the number of adults taking antipsychotic medicines during the same period.

Lucy: But the use of antipsychotic drugs by adults is considered normal at the current rate of 11 adults per 1,000 taking the drugs. In contrast, the number of children on antipsychotic medication last year was 6.6 per 1,000 children.

Lucy's argument relies on the assumption that ______.

A)normal levels of antipsychotic drug use are rarely exceeded.

B)the percentage of adults taking antipsychotic medication is always higher than the percentage of children on such medication.

C)the use of antipsychotic medication in children is no different from the use of such medications in adults.

D)Antoine is not consciously distorting the statistics he presents.

E)a rapid increase in the number of children taking antipsychotic drugs generates more fear of random violence by adolescents than does knowledge of the absolute number of children on such medications.

OA is C. While I can't find anything wrong with the OA, my question is whats wrong with D?

Although Lucy is not directly using the statistics presented, she has to assume that they are accurate to counter argue. so for that she has to believe in Antoine which means D.
Let`s consider two important general strategies:

-in assumption questions, choices that deal with someone`s motivations, or possible biases are almost always wrong (they can only be right if the argument was about someone`s motivations, or possible biases)

-and, in arguments, we always have to take arguers` evidence as true, as `given`. The denial of choice D-the idea that Antoine WAS consciously distorting his evidence-suggests Antoine was lying. But Lucy is taking it as a fact because Antoine told her to ("..the alarming fact"...).

If we took this fact away-if we denied it-it`s not that Lucy`s argument falls apart; instead, Lucy has no reason to make the argument.

You can also deny choice C to check whether it is correct. Lucy thinks she can judge whether the kids and teenagers` rate of 6.6 per 1,000 is safe by evaluating it against the `normal` adult rate of 11 per 1,000.

If we deny choice C, we have: children taking antipsychotics IS different from adults taking antipsychotics. Then, it is clear that Lucy can`t really use these stats to say there is nothing to worry about the rate of children taking antipsychotics. So, she is definitely relying on this assumption.
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by gmatmachoman » Fri Nov 06, 2009 11:17 pm
@testLuv:

Does generally GMAT asks these sort of assumptions questions??

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Denial Test

by raghavakumar85 » Sat Nov 07, 2009 9:43 am
TestLuv,

I am trying to apply denial test to assumption questions recently, but it doesn't seem to work for me. When I deny a choice, how can I tell that it should be the assumption? Is it because it changes the meaning of because it changes the tone of the passage?

Can you please explain me about denial test in brief. May be with a relatively easier example.
Thanks

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Re: Denial Test

by Testluv » Sat Nov 07, 2009 1:22 pm
raghavakumar85 wrote:TestLuv,

I am trying to apply denial test to assumption questions recently, but it doesn't seem to work for me. When I deny a choice, how can I tell that it should be the assumption? Is it because it changes the meaning of because it changes the tone of the passage?

Can you please explain me about denial test in brief. May be with a relatively easier example.
Thanks
Hi Raghava,

sure!

Let's say the author's evidence is: "all people are mortal"

Let's say the author's conclusion is: "therefore, Testluv is mortal".

What assumption does this argument depend on?

Obviously, the author is assuming that Testluv is a person.

We can check whether this is correct by using the denial test: What happens to the argument if Testluv is NOT a person? Then, clearly, the argument no longer holds.

Therefore, the idea that Testluv is a person is a necessary assumption of the argument: without it, the argument no longer holds.

So, when denying answer choice in assumption questions, ask "what if..opposite?" THEN, see if the argument falls apart. You get a distinct feeling when a choice responds to the denial test--you get a distinct feeling when an argument falls apart after denying a choice. So, if you are not getting that feeling, then the answer choice you are denying is most likely not a necessary assumption--not the answer.

(Not a lot times in teaching standardized tests that I get to use the word "feeling" but denial test is one.)
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by raghavakumar85 » Sat Nov 07, 2009 1:36 pm
Thanks Testluv,

I got it right now. I tried answering an assumption question that says about pesticides and apples. My denial test worked for it.

But, for questions where we are asked to identify what strengthens the argument, can we apply denial test? Since strengthen question supports the conclusion and also says that the assumption of the argument is true. Doesn't it work that way?

Correct me If i am thinking too far.

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by Testluv » Sat Nov 07, 2009 2:31 pm
raghavakumar85 wrote:Thanks Testluv,

I got it right now. I tried answering an assumption question that says about pesticides and apples. My denial test worked for it.

But, for questions where we are asked to identify what strengthens the argument, can we apply denial test? Since strengthen question supports the conclusion and also says that the assumption of the argument is true. Doesn't it work that way?

Correct me If i am thinking too far.
Hi Raghava,

that's great!

Answer choices to strengthen/weaken questions are always facts (the question stem will say "which of the following if true.."). Any fact that makes the conclusion more likely is a strengthener (and any answer choice that makes the conclusion less likely is a weakener).

However, these facts will usually operate through the assumption: a fact that tends to verify the assumption is a strengthener and will make the conclusion more likely to hold while a weakener will tend to refute the assumption, and will make the conclusion less likely to be true.

We can also use denial test in weaken and strengthen questions but it works a bit differently. If you are not sure if a choice is strengthening, deny it. If the denied choice clearly weakens, then that answer choice (prior to your denying it) is a strengthener.

It works because, often, it is easier to see what effect the denied choice has on the argument than it was to see what effect the original choice did.
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by raghavakumar85 » Sat Nov 07, 2009 2:49 pm
Thanks a lot !

My exam is just 2 weeks away from now. sometimes i get confused mainly in the CR section and that eats lot of my time.

Do you have any specific strategy on how to attack questions that need inferences from the arguments? It would be helpful to all of us, if not only to me.

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by Testluv » Sat Nov 07, 2009 3:01 pm
raghavakumar85 wrote:Thanks a lot !

My exam is just 2 weeks away from now. sometimes i get confused mainly in the CR section and that eats lot of my time.

Do you have any specific strategy on how to attack questions that need inferences from the arguments? It would be helpful to all of us, if not only to me.
Hi Raghava,

sure!

In inference questions, you need to treat all of the statements in the passage as necessarily true. The right answer is something that MUST BE TRUE while the four wrong answers are things that COULD or MUST BE FALSE.

In inference questions, you can also use the denial test. If you are finding a choice tempting but you're not sure, ask youself whether it HAS to be true. Ask, whether it could be false--deny it.

Then, you might say to yourself: "but wait if this choice were false, then that second sentence of the passage would be false. But because this is inference, I am supposed to treat the passage as true. So this choice HAS to be true, and is the answer."

Here is an inference question where I discuss application of the denial test: https://www.beatthegmat.com/cezzanne-s-t47562.html

And I give some tips on avoiding a common wrong answer type in inference her: https://www.beatthegmat.com/budget-trade ... 47305.html
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by xcusemeplz2009 » Sat Nov 07, 2009 8:21 pm
Testluv wrote:
raghavakumar85 wrote:Thanks a lot !

My exam is just 2 weeks away from now. sometimes i get confused mainly in the CR section and that eats lot of my time.

Do you have any specific strategy on how to attack questions that need inferences from the arguments? It would be helpful to all of us, if not only to me.
Hi Raghava,

sure!

In inference questions, you need to treat all of the statements in the passage as necessarily true. The right answer is something that MUST BE TRUE while the four wrong answers are things that COULD or MUST BE FALSE.

In inference questions, you can also use the denial test. If you are finding a choice tempting but you're not sure, ask youself whether it HAS to be true. Ask, whether it could be false--deny it.

Then, you might say to yourself: "but wait if this choice were false, then that second sentence of the passage would be false. But because this is inference, I am supposed to treat the passage as true. So this choice HAS to be true, and is the answer."

Here is an inference question where I discuss application of the denial test: https://www.beatthegmat.com/cezzanne-s-t47562.html

And I give some tips on avoiding a common wrong answer type in inference her: https://www.beatthegmat.com/budget-trade ... 47305.html

as per denial test rule or negation method mentioned by power score....if negating a choice makes the conclusion invalid then thats a correct one. However in infrence or must be true type stimulus usuaslly there is no conclusion ...then how we should implement this rule....

for eg

Certain instruments used in veterinary surgery can be made either of stainless steel or of nylon. In a study of such instruments, 10 complete sterilizations of a set of nylon instruments required 3.4 times the amount of energy used to manufacture that set of instruments, whereas 50 complete sterilizations of a set of stainless steel instruments required 2.1 times the amount of energy required to manufacture that set of instruments.
If the statements above are true, each of the following could be true EXCEPT:
(A) The 50 complete sterilizations of nylon instruments used more energy than did the 50 complete sterilizations of the stainless steel instruments.
(B) More energy was required for each complete sterilization of the nylon instruments than was required to manufacture the nylon instruments.
(C) More nylon instruments than stainless steel instruments were sterilized in the study.
(D) More energy was used to produce the stainless steel instruments than was used to produce the nylon instruments.
(E) The total cost of 50 complete sterilizations of the stainless steel instruments was greater than the cost of manufacturing the stainless steel instruments.

though the above one is an except MBT one, yet i wud like to understand how we can use a denial test for the four mbt statement , which will make it wrong ans .

thanks in advance
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by Testluv » Sat Nov 07, 2009 8:55 pm
xcusemeplz2009 wrote:
Testluv wrote:
raghavakumar85 wrote:Thanks a lot !

My exam is just 2 weeks away from now. sometimes i get confused mainly in the CR section and that eats lot of my time.

Do you have any specific strategy on how to attack questions that need inferences from the arguments? It would be helpful to all of us, if not only to me.
Hi Raghava,

sure!

In inference questions, you need to treat all of the statements in the passage as necessarily true. The right answer is something that MUST BE TRUE while the four wrong answers are things that COULD or MUST BE FALSE.

In inference questions, you can also use the denial test. If you are finding a choice tempting but you're not sure, ask youself whether it HAS to be true. Ask, whether it could be false--deny it.

Then, you might say to yourself: "but wait if this choice were false, then that second sentence of the passage would be false. But because this is inference, I am supposed to treat the passage as true. So this choice HAS to be true, and is the answer."

Here is an inference question where I discuss application of the denial test: https://www.beatthegmat.com/cezzanne-s-t47562.html

And I give some tips on avoiding a common wrong answer type in inference her: https://www.beatthegmat.com/budget-trade ... 47305.html

as per denial test rule or negation method mentioned by power score....if negating a choice makes the conclusion invalid then thats a correct one. However in infrence or must be true type stimulus usuaslly there is no conclusion ...then how we should implement this rule....

for eg

Certain instruments used in veterinary surgery can be made either of stainless steel or of nylon. In a study of such instruments, 10 complete sterilizations of a set of nylon instruments required 3.4 times the amount of energy used to manufacture that set of instruments, whereas 50 complete sterilizations of a set of stainless steel instruments required 2.1 times the amount of energy required to manufacture that set of instruments.
If the statements above are true, each of the following could be true EXCEPT:
(A) The 50 complete sterilizations of nylon instruments used more energy than did the 50 complete sterilizations of the stainless steel instruments.
(B) More energy was required for each complete sterilization of the nylon instruments than was required to manufacture the nylon instruments.
(C) More nylon instruments than stainless steel instruments were sterilized in the study.
(D) More energy was used to produce the stainless steel instruments than was used to produce the nylon instruments.
(E) The total cost of 50 complete sterilizations of the stainless steel instruments was greater than the cost of manufacturing the stainless steel instruments.

though the above one is an except MBT one, yet i wud like to understand how we can use a denial test for the four mbt statement , which will make it wrong ans .

thanks in advance
Hi xcusmeplz2009,

Please study this: https://www.beatthegmat.com/cezzanne-s-t47562.html

A true or pure inference question asks you for seomthing that can be properly inferred or must be true (same thing) based on one or more statements in the passage. All the information in an inference passage you have to treat as true.

So, in testing whether a choice must be true, you can deny a choice--take its opposite. If that would then make any part of the passage false, then you know that this is the right answer. The denial test in your head for the right answer would be something like this: "hmmm, you're tempting...could you be false....NO WAY! If you were false, then that sentence in the passage would be false! And all the info in inference passage is true. So you must be true."

Now, as for this question. Step one of the Kaplan method is to read the question stem. Here, we see it is a "could be true EXCEPT" question. So this is in the inference family, but not the same as a "pure" inference question that asks you for what must be true or what can be properly inferred (same thing).

The next thing to do is to characterize the choices. In an EXCEPT question, whatever the question stem says is what the four wrong answers are! Here: the question stem says could be true. So, the four wrong answers are things that could be true. The right answer is something the opposite of that: something that must be false.

Because the right answer is something that must be false (rather than something that must be true, as is usually the case on a GMAT inference question), it will be something that, if TRUE, would falsify information in the passage. So, the right answer is something where you would say to it: "you can't be true; if you were true, the passage would be wrong; so you must be false, and you are the right answer."
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by xcusemeplz2009 » Sat Nov 07, 2009 11:00 pm
thanks testluv
one more thing is out of scope type ans not correct for except type question?.
suppose the q stem asks all of the following is weakening/strnthng/mbt except....
if out of 5 choices 3 are weakening/strnthng or mbt
one is out of scope and last one is may be strenthening instead of weakening or may be weakening rather strengthening , or may be Cud be false rather mBT then which one to pick .....

how GMAT gives the option will it give a 4 favouring and one not favouring OR 3 favouring , 1 not favouring and 1 out of scope option....

In the given CR i find 4 and 5 as out of scope as production and cost is not disccused...2nd as cud be false...
so as per my inf B has to be the ans

pls clarify ........
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by Testluv » Sat Nov 07, 2009 11:19 pm
xcusemeplz2009 wrote:thanks testluv
one more thing is out of scope type ans not correct for except type question?.
suppose the q stem asks all of the following is weakening/strnthng/mbt except....
if out of 5 choices 3 are weakening/strnthng or mbt
one is out of scope and last one is may be strenthening instead of weakening or may be weakening rather strengthening , or may be Cud be false rather mBT then which one to pick .....

how GMAT gives the option will it give a 4 favouring and one not favouring OR 3 favouring , 1 not favouring and 1 out of scope option....

In the given CR i find 4 and 5 as out of scope as production and cost is not disccused...2nd as cud be false...
so as per my inf B has to be the ans

pls clarify ........
So, the question stem is "could be true EXCEPT?"

In this question, the four wrong answers are things that could be true. The further outside the scope of the stimulus answer choices stray, the less likely they are things that the stimulus will have proven necessarily false; and the more likely it is that they are things that could be true.

The right answer here is something that must be false. In order for the passage to have proven something necessarily false, that thing will have to lie directly within the scope of the stimulus.

Everything in the passage is necessarily true. Anything and everything outside the passage could be true or could be false.

There are three levels of truth:

Necessarily true
Possibly true/possibly false
Necessarily false

If something is only possibly true, then it is not necessarily true. And because it is not necessarily true, it could also be false. Likewise, anything merely only possibly false, because it is not necessarily false, could also be true. In other words: could be true = could be false

Must be false is the opposite of could be true.
Must be true is the opposite of could be false.

Here's a post where I discuss this issue:

https://www.beatthegmat.com/monster-of-a ... 47312.html

...BUT I don't think I've ever seen a "could be TRUE EXCEPT" question on the GMAT.

In this particular question, I think either it is a bad one or else there is a transcription error. The passage tells us there were 10 nylon sterilzations but then answer choice A (the only one I've looked at so far) refers to "the 50 nylon sterilizations."
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by raghavakumar85 » Sat Nov 07, 2009 11:30 pm
Testluv,

As you explained to the xcusemeplz2009, i tried the MBT from the link you gave in the previous post, I removed all the 4 out of scope options that could be true/ could be false but not completely false. It works!

But, my question is that, are there any chances that the out of scope answer will be the option we have to chose i.e., can it be the one option that is not true when compared to the other 4 options that COULD be true?

Pls explain.

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by Testluv » Sat Nov 07, 2009 11:39 pm
raghavakumar85 wrote:Testluv,

As you explained to the xcusemeplz2009, i tried the MBT from the link you gave in the previous post, I removed all the 4 out of scope options that could be true/ could be false but not completely false. It works!

But, my question is that, are there any chances that the out of scope answer will be the option we have to chose i.e., can it be the one option that is not true when compared to the other 4 options that COULD be true?

Pls explain.
Hi Raghava,


That's great!

I think you are asking me whether an outside the scope answer choice could ever be correct in an inference family question.

Sure: if the question asks you for what could be true (in which case the four wrong answers must be false) or if it asks you for what could be false (in which case, the four wrong answers must be true).

But this is very unlikely on the GMAT. Your chances of all your inferences questions being "properly inferred" and "must be true" are, I would estimate, well over 90%. Have you ever seen "could be true EXCEPT" questions in the OG (in the CR)?
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