Question about sufficient assumption questions?

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CardozoLaw09

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Question about sufficient assumption questions?

Postby CardozoLaw09 » Wed Jan 23, 2013 8:19 pm

In the stim if you have

A --> B as premise
C --> B as the conclusion

Why is the sufficient assumption C --> A and not the other way around ie) A --> C? Isn't the direction of the logic supposed to match premise ---> conclusion?
C-->A goes from conclusion to premise. Also, in cases where the stimulus has identical logic to that above, is it always the case that you would need to find an answer choice that links C ---> A (or ~A --> ~C as in the contrapositive)?

Question that corresponds to the above logic is: PT 38 S1 Q1

03152016

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Re: Question about sufficient assumption questions?

Postby 03152016 » Wed Jan 23, 2013 9:06 pm

.
Last edited by 03152016 on Tue Mar 15, 2016 3:30 am, edited 1 time in total.

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CardozoLaw09

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Re: Question about sufficient assumption questions?

Postby CardozoLaw09 » Wed Jan 23, 2013 9:19 pm

Perfect, thanks

bp shinners

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Re: Question about sufficient assumption questions?

Postby bp shinners » Thu Jan 24, 2013 2:46 pm

Good rule of thumb for this is that the new term that shows up in the conclusion must show up in the answer choice on the same side of the arrow as it does in the conclusion (unless it's the contrapositive of what you're looking for, in which case it will show up on the opposite side of the arrow and be negated).

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LSAT Blog

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Re: Question about sufficient assumption questions?

Postby LSAT Blog » Thu Jan 24, 2013 7:04 pm

Check out the side note in this post I did. It directly addresses your question using an example:

http://lsatblog.blogspot.com/2009/10/lo ... ption.html

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cricketlove00

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Re: Question about sufficient assumption questions?

Postby cricketlove00 » Mon Jan 28, 2013 11:31 am

Thanks so much for this. These questions were killing me before I read this.



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