PT 22, Section 2, #25

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PT 22, Section 2, #25

Postby unattended bag » Mon Jul 26, 2010 3:39 pm

If anybody has a minute and would be willing to write up an explanation of this problem, I would really appreciate it.

Thanks in advance.


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Re: PT 22, Section 2, #25

Postby NaturalLawyer » Mon Jul 26, 2010 4:09 pm

Here is my reconstruction of the argument in premise-conclusion form:

(1) 50 percent of people polled believe that elected officials should resign IF they are indicted for a crime.
(2) 35 percent of people polled believe that elected officials should resign ONLY IF they are convicted of a crime.
(3) Therefore, more people believe that elected officials should resign if indicted than believe that they should resign if convicted.

The first thing to notice is premise (2). Notice that the statement is about a NECESSARY condition for whether or not elected officials should resign rather than a SUFFICIENT CONDITION. This is indicated by the ONLY IF clause.

But both premise (1) and the conclusion (3) are about sufficient conditions. Most importantly, take a close look at the conclusion (3). It states that more people believe that IF an elected official is indicted, THEN he (or she) should resign than believe that IF an elected official is convicted, THEN he (or she) should resign.

But (2) uses an ONLY IF statement which makes the statement about necessary conditions rather than sufficient conditions.

Answer choice (B) states that the reasoning confuses a sufficient condition with a required condition. Don't be thrown off by the words "required condition". That just simply means "necessary condition".

It is important to get a good grip on necessary vs. sufficient conditions. I suggest taking a look at the powerscore logical reasoning book or the article on top-law-school regarding conditional statements.

I hope that helps! Good luck!

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Re: PT 22, Section 2, #25

Postby 3|ink » Fri Aug 27, 2010 4:49 pm

I can't believe I missed this one today. GRRRR. It's freakin basic logic. Anyway, A is wrong because we don't know how many people were polled so we can't say it was a small sample. Besides, even if we did know how many were polled, it'd be the lesser flaw compared to the other.

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