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Q5 - Planetary bodies differ from one

by dtangie23 Tue Oct 05, 2010 10:44 pm

I have no idea if I'm doing this correctly. Can someone please try to follow this reasoning and possibly correct it?

Conditional Statements:

1.
Unless the core generates enough heat for volcanic activity, surface will not be renewed.

surface renewed --> core-heat-volcanic eruption

2.
Any planetary body with a solid surface that isn't renewed is pockmarked by meteorite craters.

~surface renewed

and ----> Pockmarked by meteorite craters

solid surface


Additional Fact:

1.
Europa has a solid surface with few meteorite craters (meaning it's not heavily pockmarked)

Plugging it in:

~Pockmarked by meteorite craters --> surface renewed
(Europa) or
~solid surface

We know that Europa is solid as stated in the stimulus. So the conditional can be modified:

~Pockmarked by meteorite craters --> surface renewed
(Europa)

Plug this into the first conditional:

Europa surface renewed --> core-heat-volcanic action

So since Europa is a cold planetary body, this validates answer choice (E), which states that some of these cold planetary bodies generate enough heat for the volcanic action.
 
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Re: Q5 - Planetary bodies differ from one

by cyruswhittaker Wed Oct 06, 2010 12:42 am

Everything looks solid to me. On the surface, this looks like an intimidating problem, but when you break it down into the necessary/sufficient conditions, and then use the contrapositives, it becomes pretty simple.
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Re: PT 13 S4 Q5 Planetary bodies differ from one another

by ManhattanPrepLSAT1 Thu Oct 07, 2010 2:41 am

I second that.

dtangie23 Wrote:2.
Any planetary body with a solid surface that isn't renewed is pockmarked by meteorite craters.

~surface renewed

and ----> Pockmarked by meteorite craters

solid surface


The only thing I'd mention is that I would probably notate this a bit differently:

SS + ~SR ---> PM

SS = solid surface, SR = surface renewed, PM = pockmarked

Great work though. Most importantly, you were able to follow the chain of reasoning.
 
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Re: PT 13 S4 Q5 Planetary bodies differ from one another

by peg_city Wed Jul 20, 2011 6:20 pm

dtangie23 Wrote:I have no idea if I'm doing this correctly. Can someone please try to follow this reasoning and possibly correct it?

Conditional Statements:

1.
Unless the core generates enough heat for volcanic activity, surface will not be renewed.

surface renewed --> core-heat-volcanic eruption

2.
Any planetary body with a solid surface that isn't renewed is pockmarked by meteorite craters.

~surface renewed

and ----> Pockmarked by meteorite craters

solid surface


Additional Fact:

1.
Europa has a solid surface with few meteorite craters (meaning it's not heavily pockmarked)

Plugging it in:

~Pockmarked by meteorite craters --> surface renewed
(Europa) or
~solid surface

We know that Europa is solid as stated in the stimulus. So the conditional can be modified:

~Pockmarked by meteorite craters --> surface renewed
(Europa)

Plug this into the first conditional:

Europa surface renewed --> core-heat-volcanic action

So since Europa is a cold planetary body, this validates answer choice (E), which states that some of these cold planetary bodies generate enough heat for the volcanic action.


I'm having a hard time digesting these inferences.

The first two I get.
1.
Surfaced renewed -> Volcanic action
2.
-Surfaced renewed
+ -> Heavily marked craters
Solid Surface

3. and 4.
Old planetary bodies <S-> Few meter craters

Solid surface <S-> Old planetary bodies

I don't get how I'm supposed to attach those two last inferences to the first one. What am I doing wrong?

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Re: Q5 - Planetary bodies differ from one another

by ManhattanPrepLSAT1 Thu Jul 21, 2011 2:47 pm

peg_city Wrote:The first two I get.
1.
Surfaced renewed -> Volcanic action
2.
-Surfaced renewed
+ -> Heavily marked craters
Solid Surface

3. and 4.
Old planetary bodies <S-> Few meter craters

Solid surface <S-> Old planetary bodies


The issue is that the last two shouldn't be separated, but rather should represent one statement.

Old planetary bodies <-S-> few meteorite craters + solid surfaces

Otherwise you're right, you cannot connect it to the first two statements.
peg_city Wrote:The first two I get.
1.
Surfaced renewed -> Volcanic action
2.
-Surfaced renewed
+ -> Heavily marked craters
Solid Surface


Even these two I would adjust a bit...

1. Solid surface + Surface renewed ---> volcanic action
2. Solid surface + ~Surface renewed ---> pockmarked

adding that

3. PB <-S-> Solid Surfaces + ~Pockmarked

we can infer from 2+3...

that some planetary bodies with solid surfaces have had their surfaces renewed.

Combine that with the first premise and we can infer...

that some planetary bodies have volcanic action - best expressed in answer choice (E).


Does that make sense? or is that just a maze? Let me know if you still have questions on this one?
 
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Re: Q5 - Planetary bodies differ from one another

by lhermary Mon Jul 25, 2011 5:01 pm

mshermn Wrote:
peg_city Wrote:The first two I get.
1.
Surfaced renewed -> Volcanic action
2.
-Surfaced renewed
+ -> Heavily marked craters
Solid Surface

3. and 4.
Old planetary bodies <S-> Few meter craters

Solid surface <S-> Old planetary bodies


The issue is that the last two shouldn't be separated, but rather should represent one statement.

Old planetary bodies <-S-> few meteorite craters + solid surfaces

Otherwise you're right, you cannot connect it to the first two statements.
peg_city Wrote:The first two I get.
1.
Surfaced renewed -> Volcanic action
2.
-Surfaced renewed
+ -> Heavily marked craters
Solid Surface


Even these two I would adjust a bit...

1. Solid surface + Surface renewed ---> volcanic action
2. Solid surface + ~Surface renewed ---> pockmarked

adding that

3. PB <-S-> Solid Surfaces + ~Pockmarked

we can infer from 2+3...

that some planetary bodies with solid surfaces have had their surfaces renewed.

Combine that with the first premise and we can infer...

that some planetary bodies have volcanic action - best expressed in answer choice (E).


Does that make sense? or is that just a maze? Let me know if you still have questions on this one?


I get it, however I don't get how I'm supposed to come up with all these inferences and give the answer in such a short amount of time. It would honestly take me more then 2 minutes to read everything and come up with all the conditional logic. Is there an easier way for a question like this?
 
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Re: Q5 - Planetary bodies differ from one

by donghai819 Tue May 31, 2016 3:58 pm

A long scenario followed by a trigger... for a similar example please see 14-2-11