Conditionals

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Conditionals

by imskpwr » Sat Apr 05, 2014 7:11 pm
My cat enjoys going outside if it is not raining and if the large feral tabby cat that lives in the alley is nowhere nearby. If it is raining, my cat does not enjoy going outside, save in one circumstance: if the white Siamese cat who lives across the street is around, my cat does enjoy going outside regardless.

Which of the following do the statements above most adequately support?

If the Siamese cat is outside, Vasily's cat will ignore the large feral tabby.

If the large feral tabby is nearby, Vasily's cat will not enjoy going outside.

If it is raining and Vasily's cat is enjoying itself, then the large feral tabby must be nowhere nearby.

If Vasily's cat is enjoying going outside and the large feral tabby is nowhere nearby, then either it is not raining or the white Siamese is around.

If Vasily's cat does not enjoy going outside, then either the large feral tabby is nearby or it is not raining.

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by [email protected] » Sat Apr 05, 2014 7:21 pm
Hi imskpwr,

This is an LSAT Logical Reasoning question; the prompt is built around what's called "formal logic." This concept is NOT tested on GMAT CRs, so you shouldn't be using it for practice.

Here's the basic concept though:

When dealing with an "If X, then Y" logical statement, the equivalent would be "If Not Y, then Not X."

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by imskpwr » Sun Apr 06, 2014 1:10 pm
[email protected] wrote:Hi imskpwr,

This is an LSAT Logical Reasoning question; the prompt is built around what's called "formal logic." This concept is NOT tested on GMAT CRs, so you shouldn't be using it for practice.

Here's the basic concept though:

When dealing with an "If X, then Y" logical statement, the equivalent would be "If Not Y, then Not X."

GMAT assassins aren't born, they're made,
Rich
Agreed. I just stumbled to this q from veritas gmat q bank.
I know it is not tested in gmat from the structure, but still i want to know how to do it.

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by VivianKerr » Sun Apr 06, 2014 4:58 pm
Fun question!

Here's how I'd break this one down:

Question Rephrase: Which conclusion is MOST supported?

Given Info:

No rain + No feral = Cat enjoys
Rain = Cat does not enjoy
Rain + Siamese = Cat enjoys

The information is almost like a flow chart. Depending on certain circumstances (ran, feral, Siamese) we can arrive at two different conclusions (cat enjoys, cat does not enjoy).

The correct conclusion will be something that is strongly supported by this 'flow chart.'

(A) -- we don't have a relationship between "Feral" and "Siamese" in our flow. Incorrect.
(B) -- there are TWO requirements for "not enjoy": "no rain" AND "no feral"; this tells us nothing about the rain
(C) -- "enjoying itself" does not necessarily mean "outside." Incorrect.
(D) -- YES! This is directly supported by the "flow."
(E) -- "don't not enjoy" would mean it IS raining AND the feral IS outside. Note the use of "and" in the question stem.
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by David@VeritasPrep » Sun Apr 06, 2014 5:26 pm
This is an experimental question from the Veritas question bank. It does involve more formal logic than you would see in the Official Guide or the GMATPrep. Although it is formal logic it is not nearly to the extent of what you would see on the LSAT and can be fun in small doses like this!

I just looked up the statistics on this one - since it is in the Veritas Question Bank I can do that.

It turns out that 932 out of 1500 people have gotten this right. Actually this question actually rates at a little less than the 50th percentile. I found that interesting.
still i want to know how to do it.
Here is how you would do the question. Treat it like a normal inference question. Eliminate those answers that could be false. That is what Vivian has done so well above. You really do not need to know anything special to do this one!
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by imskpwr » Mon Apr 07, 2014 12:18 am
VivianKerr wrote:Fun question!

Here's how I'd break this one down:

Question Rephrase: Which conclusion is MOST supported?

Given Info:

No rain + No feral = Cat enjoys
Rain = Cat does not enjoy
Rain + Siamese = Cat enjoys

The information is almost like a flow chart. Depending on certain circumstances (ran, feral, Siamese) we can arrive at two different conclusions (cat enjoys, cat does not enjoy).

The correct conclusion will be something that is strongly supported by this 'flow chart.'

(D) -- YES! This is directly supported by the "flow."
If Vasily's cat is enjoying going outside and the large feral tabby is nowhere nearby, then either it is not raining or the white Siamese is around

two deductions from this:
Either,
enjoy outside + no tabby-------> no rain OR siamese

Or,

Rain and No siamese--------> not enjoy Or tabby

how could anyone of the above is derived from your flowchart?.