December 2003 LSAT
Section 2
Question 22
Radio airplay restrictions are nationally imposed regulations. The City Club has compiled a guide to all nationally i...
Replies
Naz on October 1, 2015
Conclusion: the City Club's guide covers radio airplay restrictions.Why? Radio airplay restrictions are nationally imposed regulations. The City Club has compiled a guide to all nationally imposed regulations other than those related to taxation or to labor law, neither of which Radio airplay restrictions apply to.
So: if it is neither related to taxation nor to labor law, then the guide applies to it.
P1: T or LL ==> not A
A ==> not T and not LL
P2: not T and not LL
_________________
C: A
This is an invalid contrapositive argument. We are invoking the necessary condition of our contrapositive to conclude the sufficient condition. We can never infer anything from a necessary condition. This this reasoning is flawed.
Answer choice (B) has the same exact pattern of reasoning.
Conclusion: the Garden Club awards a prize each year for coreopsis.
Why? Coreopsis is a perennial. The Garden Club awards a prize each year for each perennial other than those that are shrubs or not native to North America, neither of which apply to coreopsis.
P1: S or not NNA ==> not AP
AP ==> not S and NNA
P2: not S and NNA
_________________________
C: AP
Again, just as in the argument in the passage, we have an invalid contrapositive argument. The necessary condition of the contrapositive invokes the sufficient condition.
Hope that clears thing up! Please let us know if you have any other questions.
alymathieu on December 28, 2018
If this is an invalid argument why is it not in the flawed parallel reasoning section thenRavi on December 29, 2018
@alymathieu,Great question. This problem is a parallel reasoning question, so it's
correctly categorized. Although Naz's analysis gets us to the correct
answer, I disagree with her that this is an invalid argument. I think
it's valid.
We're first told that radio airplay restrictions are nationally
imposed regulations
RAR - ->NIR
In the stimulus, we're told that the City Club has compiled a guide to
all national imposed regulations except those related to taxation or
labor law. We can write this as
NIR and not T and not L - ->Guide
We're then told that radio airplay restrictions are related neither to
taxation nor to labor law. Therefore, we know that radio airplay
restrictions are a subset of NIR that are not T and not L.
RAR - -> not T and not L
The conclusion of the stimulus says that the City Club's guide covers
radio airplay stations. We know this to be true since the radio
airplay restrictions are a subset of the NIR that are not T and not L
RAR - ->Guide
The basic format of this argument is
A→B
B + /C + /D → E
A→/C + /D
———–
A→E
All As are Bs. We gathered a list of all Bs except Cs or Ds. A is
neither a C nor a D. Therefore A is included in the list.
This is the exact structure that we see in answer B.
C - ->P
P + /Shrub + Native - ->Prize
C - ->/Shrub + Native
Therefore, C - ->P
Does this make sense? Let us know if you have more questions!