Tough Kaplan question

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Tough Kaplan question

by Carlo75 » Fri May 30, 2008 3:06 am
Attention Deficit Disorder (ADD) is a condition characterized by an inability to focus on any topic for a prolonged period of time, and is especially common among children five to ten years old. A recent study has shown that 85 percent of seven-year-old children with ADD watch, on average, more than five hours of television a day. It is therefore very likely that Ed, age seven, has ADD, since he watches roughly six hours of television a day.

The argument above is flawed because it

A – cites as a direct causal mechanism a factor that may only be a partial cause of the condition in question
B – fails to indicate the chances of having ADD among seven-year–old children who watch more than five hours of television a day
C - limits the description of the symptoms of ADD to an inability to focus for a prolonged period of time
D – fails to consider the possibility that Ed may be among the 15 percent of children who do not watch more than five hours of television a day
E – does not allow for other causes of ADD besides television watching



Why the OA is B? PLEASE explanations
Source: — Critical Reasoning |

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Re: Tough Kaplan question

by Stuart@KaplanGMAT » Fri May 30, 2008 8:16 am
Carlo75 wrote:Attention Deficit Disorder (ADD) is a condition characterized by an inability to focus on any topic for a prolonged period of time, and is especially common among children five to ten years old. A recent study has shown that 85 percent of seven-year-old children with ADD watch, on average, more than five hours of television a day. It is therefore very likely that Ed, age seven, has ADD, since he watches roughly six hours of television a day.

The argument above is flawed because it

A – cites as a direct causal mechanism a factor that may only be a partial cause of the condition in question
B – fails to indicate the chances of having ADD among seven-year–old children who watch more than five hours of television a day
C - limits the description of the symptoms of ADD to an inability to focus for a prolonged period of time
D – fails to consider the possibility that Ed may be among the 15 percent of children who do not watch more than five hours of television a day
E – does not allow for other causes of ADD besides television watching



Why the OA is B? PLEASE explanations
The argument in the stimulus is analogous to:

Smoking causes cancer.
Shelly has cancer, therefore Shelly must be a smoker.

Causation arguments are very common on the GMAT.

We can abstract the argument as:

X causes Y.

Someone has quality Y, therefore he also has quality X.

There are a number of different flaws in this line of reasoning. On the GMAT, we'll often see one of the following in the correct answer:

1) there are other ways to get quality Y
2) Y often occurs in the absence of X

Answer choice (b) is a variation of (2) on the list: the author fails to consider how many people have condition Y without having precursor X.
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by Carlo75 » Sat May 31, 2008 12:39 am
Now it's clear ... many thanks

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by khanshainur » Tue May 10, 2016 4:52 am
i feel it's B