Flawed Reasoning

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Flawed Reasoning

by ajaysingh24 » Tue Jun 24, 2014 10:44 am
Only senior citizens enjoy doing the daily jumble. So Aesha must not be a senior citizen, because she does not enjoy doing the daily jumble.

Which of the following arguments exhibits the same flawed reasoning as the above?

a)Only in March does Rodrigo choose to holiday in Spain. It is March, but Rodrigo is in Japan. So he must not be
going to Spain.
b)Only a true pet lover could adopt Marley. Thus, since Michael is not adopting Marley, he must not be a true pet
lover.
c)Only geologists enjoy the amethyst exhibit at the town fair. So Mr. Franz must not enjoy the amethyst exhibit,
because he is not a geologist.
d)Since the animal in front of us is a penguin, it follows that we are in Antarctica, since one only encounters
penguins in the wild when one is in Antarctica.
e)Only the best chefs can make compelling vegan escargot. So Rasheed must be able to make compelling vegan
escargot, since he is one of the world's best chefs.

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by GMATGuruNY » Wed Jun 25, 2014 3:11 am
ajaysingh24 wrote:Only senior citizens enjoy doing the daily jumble. So Aesha must not be a senior citizen, because she does not enjoy doing the daily jumble.

Which of the following arguments exhibits the same flawed reasoning as the above?

a)Only in March does Rodrigo choose to holiday in Spain. It is March, but Rodrigo is in Japan. So he must not be
going to Spain.
b)Only a true pet lover could adopt Marley. Thus, since Michael is not adopting Marley, he must not be a true pet
lover.
c)Only geologists enjoy the amethyst exhibit at the town fair. So Mr. Franz must not enjoy the amethyst exhibit,
because he is not a geologist.
d)Since the animal in front of us is a penguin, it follows that we are in Antarctica, since one only encounters
penguins in the wild when one is in Antarctica.
e)Only the best chefs can make compelling vegan escargot. So Rasheed must be able to make compelling vegan
escargot, since he is one of the world's best chefs.
Map out the PIECES OF THE PUZZLE:
If someone enjoys doing the daily jumble, then he/she must be a senior citizen (since no other type of person enjoys doing the daily jumble).
Aesha does NOT enjoy doing the daily jumble.
Thus, Aesha is NOT a senior citizen.


The correct answer choice must match the map above.
Note that the pieces of the puzzle might appear in a DIFFERENT ORDER.

B: Only a true pet lover could adopt Marley. Thus, since Michael is not adopting Marley, he must not be a true pet lover.
Map of this answer choice:
If someone adopts Marley, then he must be a true pet lover (since no other type of person would adopt Marley).
Michael is NOT adopting Marley.
Thus, Michael is NOT a true pet lover.

A perfect match!

The correct answer is B.
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by Brent@GMATPrepNow » Wed Jun 25, 2014 7:13 am
ajaysingh24 wrote:Only senior citizens enjoy doing the daily jumble. So Aesha must not be a senior citizen, because she does not enjoy doing the daily jumble.

Which of the following arguments exhibits the same flawed reasoning as the above?

a)Only in March does Rodrigo choose to holiday in Spain. It is March, but Rodrigo is in Japan. So he must not be going to Spain.

b)Only a true pet lover could adopt Marley. Thus, since Michael is not adopting Marley, he must not be a true pet lover.

c)Only geologists enjoy the amethyst exhibit at the town fair. So Mr. Franz must not enjoy the amethyst exhibit, because he is not a geologist.

d)Since the animal in front of us is a penguin, it follows that we are in Antarctica, since one only encounters penguins in the wild when one is in Antarctica.

e)Only the best chefs can make compelling vegan escargot. So Rasheed must be able to make compelling vegan escargot, since he is one of the world's best chefs.
This question smells like an LSAT question (not unlike this recent post of yours: https://www.beatthegmat.com/vasily-cat-t ... tml#722154).

In LSAT terms, we can summarize the flawed argument as follows:
If J then S
notJ then notS

Here, J = enjoy doing the daily jumble
And S = is a senior citizen

Check the answer choices.
A) Only in March does Rodrigo choose to holiday in Spain. It is March, but Rodrigo is in Japan. So he must not be going to Spain.
Let HS = holiday in Spain
Let J = in Japan
Let M = March
So, this argument can be summarized as follows:
If HS then M
M + J then notHS

Doesn't have same format.

B) Only a true pet lover could adopt Marley. Thus, since Michael is not adopting Marley, he must not be a true pet lover.
Let AM = adopt Marley
Let PL = pet lover
So, this argument can be summarized as follows:
If AM then PL
notAM then notPL

Has the same format.

Answer: B

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by trgtgmat2013 » Wed Oct 08, 2014 8:05 pm
Can you please explain why option C is not the answer??

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by GMATGuruNY » Wed Oct 08, 2014 8:24 pm
trgtgmat2013 wrote:Can you please explain why option C is not the answer??
Follow the colors.

Passage:
Only senior citizens enjoy doing the daily jumble. So Aesha must not be a senior citizen, because she does not enjoy doing the daily jumble.
Answer choice C:
Only geologists enjoy the amethyst exhibit at the town fair. So Mr. Franz must must not enjoy the amethyst exhibit, because he is not a geologist.


The color pattern in C does not match the color pattern in the passage, indicating that the pattern of reasoning in C differs from that in the passage..
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by Paras_0111 » Sat Sep 10, 2016 6:46 am
Why can't the answer be E? The questions is "Which of the following arguments exhibits the same flawed reasoning as the above?", and not the same structure as above.

The reasoning in the question is that since only senior citizens enjoy the daily jumble, all senior citizens will enjoy the daily jumble. So Aesha must not be a senior citizen.

The same flawed reasoning is visible in E which claims that since Only the best chefs can make compelling vegan escargot, all best chefs should make compelling vegan escargot. So Rasheed must be able to make it.

Both statements use the same flawed logic of saying the entire demographic should be able to do something that only a particular set within that demographic can do.

Please clarify. Thank you!