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#16- Although all birds have feathers and all birds have

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student987
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Hello! I’m completely confused about this question. (I crossed out all answer choices.) I’m wondering (1) why (B) is the correct answer, (2) how to solve this kind of problem fast, and (3) if this (rather tricky?) parallel reasoning question comes up typically in more recent tests.

So given that the stimulus is: “all birds…all birds…some birds,” I thought (B) is wrong because of the structure “some chairs…other chairs…Therefore, not all chairs.” (Difference in "all" (stimulus) and "some" (answer (B)))

I also thought the stimulus lacks an argument (that is, it's just a fact set), so it doesn't match (B).

I'd appreciate any help!
Shannon Parker
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student987 wrote:Hello! I’m completely confused about this question. (I crossed out all answer choices.) I’m wondering (1) why (B) is the correct answer, (2) how to solve this kind of problem fast, and (3) if this (rather tricky?) parallel reasoning question comes up typically in more recent tests.

So given that the stimulus is: “all birds…all birds…some birds,” I thought (B) is wrong because of the structure “some chairs…other chairs…Therefore, not all chairs.” (Difference in "all" (stimulus) and "some" (answer (B)))

I also thought the stimulus lacks an argument (that is, it's just a fact set), so it doesn't match (B).

I'd appreciate any help!


When dealing with parallel reasoning, and diagramming arguments, the order in which the author places the conclusion and the premises does not effect their logical relationship.
I would diagram the stimulus as 1. All birds have feathers and wings. C. Some birds do not fly. 2. for example...use their wings in a different way. 3.penguins use.... 4. Ostriches use...
Here the conclusion is that some birds do no fly.

Answer choice B would be diagrammed as follows: 1. Some chairs... 2. and other chairs...
C. Therefore, not all chairs are used... 3. despite the fact that all chairs have a seat and some support.

While the stimulus has an extra "premise," #2 is really a summary of 3 and 4. So if we rearrange answer choice B to go 3,C,1,2. We can see how it follows the same logical pattern as that of the stimulus by presenting characteristics that every member of a class contains, then presenting a conclusion that that not all members of the class use those characteristics in the same manner, and then giving two examples of how different members of the class use those characteristics differently.

Yes, this type of parallel reasoning question comes up with great regularity. The best way to go attack these types of questions is the way I did above. Become more efficient with diagramming the arguments, and you will be able to master these questions in no time.

Hope this helps,
Shannon