Re: Setup and Rule Diagrams

[Dave Killoran]

Setup and Rule Diagram Explanation

This is an Advanced Linear: Balanced, Identify the Possibilities game.

This is a challenging game made considerably easier by applying the right technique, which, in this case, is to identify each of the possibilities. Some of the “hardest” games on the LSAT are best attacked with this technique, and once the correct technique is applied, the game no longer seems as difficult. An examination of all LSAT games makes it clear that the test makers expect you to have the ability to identify “limited solution set” scenarios when they occur. In this game, there are a large number of rules, and so it is not surprising that there would be some powerful inferences. Let’s look at each rule and develop the case for showing the possibilities.

The basic structure of the game from the scenario is as follows:

The first rule establishes that J and K are on the same team. Normally this would be a represented as a vertical JK block, but the second and fourth rules establish that K and N are on different teams, and that N is on team Y (along with M). Thus, accounting for the interaction of the first, second, and fourth rules, J and K are on team X, and N and M are on team Y:

The third rule indicates that R runs in an earlier leg than P:

From this rule, we can infer that R can never run the fourth leg, and P can never run the first leg:

The fifth rule establishes two more Not Laws, this time for J and M on the third leg:

The sixth rule stipulates that K and L run second. We have already established that K is on team X, so L must be on team Y:

The seventh and final rule indicates that O runs fourth:

At this point, most students continue on to the questions. But, there are more inferences to be made, and these inferences come from examining the most restricted open spot on the diagram: the third leg. From the fifth rule, the third leg cannot be run by J or M. But, because of the other rules, we can also eliminate K, L, and O from running third. Thus, J, M, K, L, and O cannot run the third leg, leaving only N, P, and R available to run third. But, from the third rule, R must run an earlier leg than P, which means that both P and R cannot run third simultaneously. By Hurdling the Uncertainty then, we can infer that N must run third. And, from the fourth rule, we know that N is on team Y. Thus, N must run third for team Y, and P or R must run third for team X:

That N must run third for team Y is the key inference of the game, and it destroys questions #21, #22, and #23.

While making the inference that N is third is critical for success in this game, there are additional inferences to be made, namely on the first leg. From the third rule, P can never run first, and from the other inferences and rules K, L, M, and O can also be eliminated from running first. With those five people eliminated, only J, M, and R can run the first leg. As J is on team X and M is on team Y, we can infer that J or R must run first for team X, and M or R must run first for team Y.

In evaluating this setup, three of the people are placed, and every other position has either a dual-option or split-option. Clearly, the game has significant inherent limitations, which suggests that the best approach is to Identify the Possibilities.

There are four possibilities: two when O is on team X, and two when O is on team Y:

Possibility #1: O on Team X, P runs the third leg

When O is on team X and P runs the third leg on team X, then J must run the first leg on team X (that is the only available space on team X for J) and R must run the first leg on team Y, forcing M to run the fourth leg on team Y:

Possibility #2: O on Team X, P runs the fourth leg

When O is on team X and P runs the fourth leg on team Y, then R must run the third leg on team X. J must run the first leg on team X and M must run the first leg on team Y:

Possibility #3: O on Team Y, P runs the third leg

When O is on team Y and P runs the third leg on team X, then M must run the first leg on team Y (that is the only available space on team Y for M). R must then run the first leg on team X, and J must run the fourth leg on team X:

Possibility #4: O on Team Y, P runs the fourth leg

When O is on team Y and P runs the fourth leg on team X, then M must run the first leg on team Y (that is the only available space on team Y for M). R must then run the third leg on team X, and J must run the first leg on team X:

With these four possibilities in hand, the questions can be solved quickly.

[jlfranzetti]

Hi - I am wondering if someone could offer an explanation of how to best set-up this game? Would this be a good game to utilize templates? It took me way too long when I did the game on a practice test...I wondering what the best approach is/perhaps I am missing some inferences?

[Dave Killoran]

Hi J,

Thanks for the question! This was by far the hardest game on this LSAT, so the fact that you had some difficulty with this isn't really surprising, and it shouldn't bother you too much. That said, the goal is always identify and eliminate any problems you encounter, so let's take a look at this more closely and see if we can figure this one out.

You are correct about the best approach here—this is a Template game, and using that approach makes this game a lot easier. In a nutshell, there are four possibilities: two when O is on team X, and two when O is on team Y. They are as follows:

• Possibility #1: O on Team X, P runs the third leg
  Possibility #2: O on Team X, P runs the fourth leg
  Possibility #3: O on Team Y, P runs the third leg
  Possibility #4: O on Team Y, P runs the fourth leg

Also, there is a key inference in this game, namely that N must run third for team Y. This inference destroys questions #21, #22, and #23 in very short order. Fortunately, the template approach helps you find that inference.

So, tough game for sure, and templates really help. Finding the one big inference helps you knock out several questions, and gets you back the time that you lose in creating the templates.

Please let me know if that helps. Thanks!

[jlfranzetti]

Thank you, that helps a lot!

[bella243]

Is this an Advanced Linear Game?

[Adam Tyson]

It sure is! It's linear because we are setting up an order of 1 through 4, and Advanced because we need two rows "stacked" on that order, one for each of the two teams. That's all "advanced" means in this context - multiple rows over an ordered base.

[srr021]

Hello!

I did not see the templates while I was setting up my game, but after having figure out what the four exact possibilities are, I can see that this game can actually go by quickly, that is if you see the templates. How exactly do you train yourself to see templates? I don't want to force templates on a game where it would actually be a waste of time, but I also want to train myself to see them when they are available.

Thanks in advance!

[Rachael Wilkenfeld]

Hi srr,

There are differences in opinions on this---some folks like using templates much more than others. I will say that one of the most helpful guidelines I've found was on our blog here. The basic idea is that you start a template structure if you find a situation where a 50/50 split could lead you to make other inferences. Just the 50/50 split by itself isn't enough. You want to make sure you can learn something else about the game from it.

Check out the blog---I know it helped turn me much more template friendly than I was. In order to do well on the modern exam, you really need to be open and comfortable with the templating option.

Hope that helps!