Carl is clearly an incompetent detective. He has solved a smaller perc

Question

Carl is clearly an incompetent detective. He has solved a smaller percentage of the cases assigned to him in the last 3 years—only 1 out of 25—than any other detective on the police force.

Which one of the following, if true, most seriously weakens the argument above?

A. Because the police chief regards Carl as the most capable detective, she assigns him only the most difficult cases, ones that others have failed to solve.

B. Before he became a detective, Carl was a neighborhood police officer and was highly respected by the residents of the neighborhood he patrolled.

C. Detectives on the police force on which Carl serves are provided with extensive resources, including the use of a large computer database, to help them solve crimes.

D. Carl was previously a detective in a police department in another city, and in the 4 years he spent there, he solved only 1 out of 30 crimes.

E. Many of the officers in the police department in which Carl serves were hired or promoted within the last 5 years.

Bunuel · Accepted Answer

OFFICIAL EXPLANATION

The structure of the argument is simple, and it is easy to see why the premise does not undeniably prove the conclusion. The answers contain several predictable forms, and this is the type of question you should quickly destroy. You do not need to spend a great deal of time trying to find a specific pre-phrased answer because there are so many possibilities, and the answers can be eliminated without a great deal of time spent considering which are Losers and which are Contenders. The stimulus uses a premise about success rate to form a conclusion about Carl’s competency as a detective. Ask yourself—does the premise prove the conclusion? No, because there are many factors that could have affected Carl’s performance. In this sense, the stimulus has incomplete information, and we should try to discover a relevant piece of information in one of the answer choices that will shed more light on why Carl’s success rate is so low. Use this knowledge to make a general pre-phrase that indicates you are looking for a piece of information that shows Carl’s success rate is not as low as it seems or that other factors limited Carl’s performance.

Answer choice (A): This is the correct answer.  We discover that Carl receives the hardest cases, and one would expect that the hardest cases would yield a lower success rate. Notice that this answer does not attack the premises. Even though they are still true, the conclusion is undermined by the new evidence. This is typical of most Weaken questions answers—the premises are not addressed and the focus is on the conclusion.

Answer choice (B): This answer is irrelevant. It tries to use the opinion of others about Carl’s performance in one capacity to refute facts about his performance in another capacity. Personalize the answer—is this the answer you would offer to weaken the argument against Carl if he was your friend?

Answer choice (C): This is an Opposite answer that strengthens the claim that Carl is incompetent by showing that Carl was not deprived of certain resources for solving cases.

Answer choice (D): This is another Opposite answer that strengthens the claim that Carl is incompetent. This time, the answer shows that Carl has a previous record of poor performance.

Answer choice (E): This answer goes beyond the scope of the argument by discussing the promotions of other officers. These promotions do not impact Carl’s job and no information is given about Carl’s promotions. If you are thinking that perhaps Carl’s poor performance is a result of dissatisfaction over the promotions of others, then you are assuming too much.

DinoPen · Answer

Carl is clearly an incompetent detective. He has solved a smaller percentage of the cases assigned to him in the last 3 years—only 1 out of 25—than any other detective on the police force.

Which one of the following, if true, most seriously weakens the argument above?

Essentially the passage is telling us that Since Carl solves so few cases, this means that he is incompetent.

A. Because the police chief regards Carl as the most capable detective, she assigns him only the most difficult cases, ones that others have failed to solve.
 This directly weakens the argument above. Since the cases are really difficult, it is to be expected that so few of them are solved. Also, this strengthens the notion that Carl is a competent detective.

B. Before he became a detective, Carl was a neighborhood police officer and was highly respected by the residents of the neighborhood he patrolled.
 This is entirely irrelevant; we don't care what he was before a detective.

C. Detectives on the police force on which Carl serves are provided with extensive resources, including the use of a large computer database, to help them solve crimes. 
This strengthens the argument that Carl is incompetent since he has lots of resources to make his job even better.

D. Carl was previously a detective in a police department in another city, and in the 4 years he spent there, he solved only 1 out of 30 crimes. 
Same reasoning as B. Also, the rate at which he is solving these crimes does not really matter since we don't know what quality these crimes are.

E. Many of the officers in the police department in which Carl serves were hired or promoted within the last 5 years. 
This does not effect Carl's competency himself. These are external factors that neither supports nor weakens the argument here.

achloes · Answer

Weakener: police chief believes in quality > quantity and assigns cases that others can't solve. Author would revise his position

Mild weakener: Carl was a respected member of the force therefore unlikely to be incompetent. Author might justify his position by saying that he’s not good at being a detective or that he's worse at his job than he was before

Mild strengthener: fewer cases solved despite many resources. Author might agree by saying that he’s bad at his job compared to others

Mild strengthener: past record of low hit rate. Author might agree by saying that he hasn’t improved

Mild weakener: Carl is working with top talent. Author might justify by saying that he's still incompetent for the job of a detective

VerbalBot · Answer

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Carl is clearly an incompetent detective. He has solved a smaller perc

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Carl is clearly an incompetent detective. He has solved a smaller perc

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