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I tried this game for the second time after a five months period, I got all questions right just under the target time but I spent nearly two minutes looking at the conditional rules to find some kind of deep inference which was a huge waste of time. Is it ever a good idea to look for deep inference when there are already like lots of conditional rules. I am not really sure when to stop and hit the questions. Do you have any rule of thumb that could help?

https://classic.7sage.com/lsat_explanations/lsat-22-section-3-game-4/

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I was wondering if anyone could help me out here. Always had trouble understanding this concept.

1. Say I am negating [A and B]. I know this turns to [/A or /B]. Does this or mean that BOTH A and B are out? I know it means either A is out, or B is out but can both possibly be out?

2. Conversely, if I was negating [/A and /B], I know this becomes A or B. Does this or mean that BOTH A and B could possibly be in? I know it means either A is in, or B is in, but can both possibly be in?

Not entirely sure when the "inclusive" or applies or not. Thanks a lot guys!

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So I was watching a thing on Netflix about algorithms and, all of a sudden, the guy starts explaining what I think I recognize as the weird game from PT 77. I checked it out, and sure enough: It’s a really simplified version of the Gale-Shapley algorithm which won a Nobel Prize in 2012. I don’t know anything about algorithms, but I wonder if there are other well known algorithms that could appear in the games. I think some basic, common algorithms would make for a really interesting and potentially somewhat relevant study. Certainly a familiarity with the Gale-Shapley algorithm would have made 77 G3 a breeze. It’s probably a bit far reaching to include in LSAT study proper, but I think it would be an interesting side project that could develop some relevant skills and teach exactly the kind of abstract thinking which is so important on Games and especially when weird games pop up.

So anybody know any cool algorithms they think would be worth checking out?

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JY is recommending reading the LR question stem first and figure out what question type it is before moving on the the stimulus, which I fully agree and find useful.

However, there are some question stems referring to a specific part of the stimulus and it probably won't make sense if you read it first. (here is an example where JY recommends returning to the questions stem later: https://classic.7sage.com/lsat_explanations/lsat-25-section-4-question-05).

So, my question is, what to do with an LR question stem that has a lot of contextual information? Do I just stop thinking about it if I found the question stem containing too many contextual information? Or do I try to figure out a bit what is going on, who the question stem is referring to, etc. and carry the question stem when reading the stimulus? For example, in the example above, should I just skim the question stem and return to it later after reading the stimulus, or should I try to figure out that I am going to support Zimbabwe's argument and then read the stimulus?

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When doing games, I like to attempt to solve as many probabilities as possible before going on to the questions. In short, spend time upfront in order to save time when answering questions.

However, after doing four or more boards, I begin to realize that there are too many probabilities to solve in order to complete the game in a good time.

My question is, are there any clues to look out for to help me not attempt to solve all probabilities?

How can you tell that it is not better to try to solve everything up front????

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Hello!

My last few preptests have been roughly the same in terms of score (164 average) but my LG score has been decreasing rapidly. For example, the last few preptest have been -1, -2, -3, -5, and -7, respectively, on LG. I was just wondering if anyone else has gone through this and if you could recommend a plan of action to fix this before the June test. I was thinking about going back and redoing all of the lessons, and focusing more on fool proof review, but I am not sure what else to do.

Thanks!

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I'm having trouble applying contrapositives because in many instances they seem like bunk. Specifically, it seems like they require unsupported assumptions other than those that can be derived from game rules. Here is an example:

A group of three must be selected from the variables, A, B, C, D, & E:

1. If C is not selected, then B is not selected

2. D and E cannot both be selected

3. In order for A to be selected, B must be selected.

According to the study guide that I'm using, the contrapositive of rule 1 is, if B -> C. As I see it, although B -> C may be true there is nothing that requires it to be true. To my mind and contrary to the contrapositive of rule 1, it is also possible, although not required under the rules that if B is selected then C is still not selected. That being said, contrapositives are a proven concept and its unlikely that I'm right and my study book is wrong, so what am I missing, what systematic leap in logic am missing to make the concept of contrapositives useful on the LSAT? Thanks

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I have been studying logical reasoning stimuli that include a sentence about what someone OTHER than the author says, usually near the start of the paragraph. I call these the "some people say" statements. They are different from "expert testimony," which supports the conclusion. These "some people say" statements do NOT support the conclusion. In fact, after looking at them carefully, it looks like almost every conclusion in a "some people say" stimulus is a simple negation of the "some people say" statement.

I like the term "antithesis" for these statements, since the "thesis" of the stimulus is the conclusion and the "some people say" text is the logical opposite of that.

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I would love to know if anybody can find any counterexamples to this "some people say" rule. If not, then it would provide a simple and teachable logical reasoning shortcut. Just "find the anthithesis" near the top of the stimulus, negate it, and find the evidence to support that negation. It's easy to find if you know what you're looking for.

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Hey Guys,

Needed some help with diagramming a couple of sentences into lawgic and their contraceptives.

1. If Aliens or Ghosts are in the house, then Tim and John are not in the house...Is the info I have written below correct?

- The way I have diagrammed this is like: A or G --> /T and /J. Taken further, this becomes: A --> /T, A --> /J ; G --> /T, G --> J. If Aliens are in the house, then Tom is not there. If Aliens are in the house, then John is not there. If Ghosts are in the house, then Tom is not there. If Ghosts are in the house, then John is not there.

- Contrapositive: T or J --> /A and /G. Taken further, this becomes: T --> /A, T --> /G ; J --> /A, J --> /G. If Tom is in the house, then Aliens are not the house. If Tom is in the house, then Ghosts are not in the house. If John is in the house, then Aliens are not in the house. If John is in the house, then Ghosts are in the house.

2. Totally confused about diagramming "Tom will play really well for his soccer team if John or Bill, but not both, play on the same team as him."

I understand that John or Bill, but not both will be diagrammed as /J (--) B, where contrapositive is J (--) /B. But how do I diagram the info about Tom. Is this correct? /J (--) B --> T? If yes, what will be the contrapositive?

Thanks for your help, as always.

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Hi, I'm a bit confused with the rule "M and N cannot be selected together."

Is this a biconditional with never together always apart? so, M (--) ~N

Or do I use 'cannot' and think of it as group 4? so, M --> ~N

Which one would be correct?

Thanks for the help.

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I need confirmation whether my understanding of OR rule is correct.

There is a rule in the last game of PT24 that says: G cannot be prescribed if both N and U are prescribed.

N & U -->/G

Contrapositive= G --> /N or /U

So there are 3 possibilities if the contrapositive is triggered: 1) N is out 2) U is out or 3) N and U are both out.

If I CHANGE the rule to G --> N or U, would 3 possibilities be 1) N is in 2) U is in or 3) N and U are both in?

Is it correct to consider OR in the above examples as inclusive(and/or), not exclusive?

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I was going through the core curriculum and encountered this weakening question: https://classic.7sage.com/lsat_explanations/lsat-27-section-4-question-18

I chose C, and the correct answer choice turned out to be B.

After going through the video, I understood that answer choice B is correct. But I still couldn't figure out why C is wrong. In the video, the explanation given is that "if they (book publisher) do make sizable money, they would continue doing it. The fact that they stop makes it even less reasonably that it is a money-grab... therefore C is incorrect".

But why? If C makes it less reasonable for book publisher to be money-grab, then it weakens the argument.

I wonder if anyone can help me on that...

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One of the RC videos that I watched mentioned that when something (call it X) happens more & more frequently, it does not mean that X happens most of the time. But I read it from one of the PowerScore posts that "more often than not" means MOST. They sound quite similar to me, so I'm not sure how to make a distinction between them. If I change it to "X happens more & more frequently THAN NOT" would it equate to most?

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I have been analyzing all the June 2007 (public domain) questions one by one, and find that they all neatly fit into very neat symbolic argument patterns--except for Section II Question 24. I would appreciate any comments on this particular question, especially if someone can help me write up a symbolic logic representation of it.

Please don't post full questions on the discussion forums, even if this is a free PT! You can see the question and explanation here:

https://classic.7sage.com/lsat_explanations/lsat-june-2007-section-2-question-24

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Hey All,

Had a question that I was confused about. Statement is, "People who aren't handsome are happy". Isn't the logical indicator "not" here, meaning it is in group 4 (Negate Necessary). Translated into lawgic, shouldn't this be, "Happy -> /Handsome ; Handsome -> /Happy". However, in the lessons, I found it to be " /Handsome -> Happy ; /Happy -> Handsome".

Any help would be appreciated. Thank you for reading this.

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I'm currently working on the logic games bundle. While I've been getting -1 or -2 per game untimed I continue to test every answer choice even after getting an answer just to be sure it's correct. I'm wondering if this will hinder my speed while doing actual timed games. Should I just pick the correct answer and continue or actually double check. At this point I'm focusing on accuracy not speed. Any comments would help. Thank you :)

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I'm having the hardest time improving my timing on games. I can get the questions right but I can't do them fast enough to finish all four games-- on average I only get through 3 games. I'm doing my practice using Jy's method -- I can improve my timing on games that I've done over again. But I can't improve my timing on games I've never done before. Any tips are greatly appreciated.

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I'm really stuck. I understand that the correct answer is A, but I can't diagram the logic out. I'm fairly certain it involves subsets, which has always thrown me. So if anyone knows how, please share!

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I got this one right, and I was able to easily eliminate C-E, but I don't understand how to eliminate B.

I spent a lot of time debating between A and B. I chose A as the right answer because if urban populations have doubled in the past decade then it does not indicate an increase deaths but rather indicates the population was the same amount of deaths as before SO it is not an increased amount of deaths proportionate to the death rate.

Can someone please explain B to me!? Thanks!!!

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