Setup and Rule Diagrams

[Dave Killoran]

Setup and Rule Diagram Explanation

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

The game scenario creates a setup where five cars are washed in order, with each car belonging to a certain individual and each car receiving a particular type of wash. Because each position has both a car owner and a wash type, this is an Advanced Linear game, and the basic scenario appears as follows:

PT30-Dec 1999 LGE-G3_srd1.png

The first rule establishes that the first car does not receive a super wash, although at least one car does. This means that the first car receives a regular or premium wash:

PT30-Dec 1999 LGE-G3_srd2.png

The second rule establishes that exactly one car receives a premium wash:

PT30-Dec 1999 LGE-G3_srd3.png

The third rule indicates that the second and third cars receive the same wash, which cannot be a premium wash according to the second rule. Thus, the second and third washes are either regular or super:

PT30-Dec 1999 LGE-G3_srd4.png

The fourth and fifth rules create a super-sequence of the individuals:

PT30-Dec 1999 LGE-G3_srd5.png

This sequence controls the game and creates four possible orders of the cars:

PT30-Dec 1999 LGE-G3_srd6.png

Given that there are also four rules about the washes, after we consider the final rule we will examine those possibilities above in connection with the washes.

The final rule indicates that M and the car immediately before M receive regular washes:

PT30-Dec 1999 LGE-G3_srd7.png

Linking the four rules about wash types to the four possible car orders above yields four basic templates:

PT30-Dec 1999 LGE-G3_srd8.png

Templates #3 and #4 contain exactly one possibility each. With the templates, the game is relatively easy and certain inferences such as O is always regular, and the second wash is always regular, are made clear.

Note: if you do not wish to make this a multi-stacked game, you can use subscripts for the type of wash each car receives, e.g. MR .

[alee]

Hi guys,

This question refers to Game 3 of the December 1999 LSAT. A key inference seems to follow by combining the order of the 5 cars V>O>M>F, (with T being anywhere after V) with 2 rules: firstly that M's car and the car immediately before both receive regular washes, and secondly that the 2nd and 3rd cars receive the same kind of wash. This leads to the inference that O must receive a 'r'egular wash.

I set the game up like this:

V O M F T _ _ _ _ _

rsp _ _ _ _ _
1 2 3 4 5

It seemed that dealing with questions 12-14 really required discovering the key inference that O must receive a 'regular' wash. I only discovered this by writing out all the possible orderings: VOMFT, VOMTF, VOTMF, VTOMF, and analysing these together with the rules and setup diagram. But this seems like a bit too time consuming...

Could you recommend any better/faster strategies at dealing with this game?

Thanks for the help!

[Dave Killoran]

Hi Alee,

Actually, that is the fastest (and surest) strategy to solving this particular game. The presence of four major directions suggests that you should explore each at least briefly, and although setting that up takes an extra minute, you can then answer the questions extremely quickly (especially when the other rules are factored in).

That extra setup time is a hallmark of Identifying the Possibilities, but then you get the dual benefit of answering the questions with 100% certainty and absolute speed.

Thanks!

[LSAT2018]

How do I arrive at the inference that O must receive a r'egular wash? Is it because the second and third car must always receive a regular wash, and O can either be in the second or third position?

[Adam Tyson]

Not just that O CAN be 2nd or 3rd,LSAT2018, but that O MUST be 2nd or 3rd! He can't go first, since he has to be after V, and he can't go 4th or 5th since he has to be before both M and F. See alee's walk-through of the process at the top of this thread and you'll see how that inference came to be.

Keep at it!

[Tajadas]

Hi, what kind of game is this, other than Identify the Possibilities?

[Jeremy Press]

Hi Tajadas,

It's an Advanced Linear game! That's because we have one set of variables (the cars) that we need to track the order of (the order that they're washed in), but for each car we also have to track the type of wash (Regular, Super, Premium) it receives. And the best way to do that is to stack an additional line on top of the base line of cars (to account for the Regular, Super, Premium variable set), giving you the usual "stacked linear" organization of an Advanced Linear game.

I hope this helps!

Jeremy