Setting Up Basic Ordering Games

Back to: LSAT Logic Games

Now we are going to talk about how to make your main diagram for solving a basic ordering game. The main diagram is the drawing of your board, game pieces, and rules. It contains all the work you do before you get to the questions. This includes all the rules for the prompt (scenario + rules), and any inferences you can make using those rules.

The main diagram is your way of visualizing the game as a whole. With your main diagram, you will have an easier time picturing where things can go, as well as an easy reference to the rules of the game.

Ordering games are just what you would think they are from the name–you’re given a set of variables and a list of rules governing the acceptable order of those variables, and then you have to figure out how the variables can be ordered without breaking any of the given rules.

The first thing you have to do when making your main diagram is to list your pieces and draw your empty game board.

Let’s go through this process with a typical basic ordering game prompt:

A delivery van is set to deliver soda to six grocery stores—Frank’s, Gerry’s, Himmelman’s, JiffyMart, Keeble’s, and Lifeway—over the course of six consecutive days. Exactly one delivery is made each day, and soda can’t be delivered to any store twice.

Looking at this prompt, what we have is two sets of variables: six consecutive days and six grocery stores.

For the six consecutive days, you already know they go in order, 1 through 6 (since that’s what consecutive means). That’s typical of an ordering game. There is always going to be one variable set—days of the week, aisles in a store, floors of a building, etc—that has a natural order to it. That variable set is used as the base of your game board. The other set of variables (in this case, grocery stores), will be arranged within that game board.

Always, always use the group of variables that you already know the order of as your game board (the base). Here, that’s the days. With six days in total, this is what your base will look like:

The other variables (the grocery stores) are going to be going into these slots that you’ve made. They are the game pieces. However, it would be a major waste of time to write out the full name of every grocery store each time you need to place one of these variables. Instead, we will just use the first letter of each one to represent it.

Write them out big at the top left of your main diagram like this:

Pretty simple huh? Now you do not need to keep referring back to the prompt to see what your variables are. Just refer to this list. In fact, you might as well forget at this point what “F” or “G” or any of them even stand for. From now on, they are just game pieces that move around.

Why? Because when you are solving games, it is best to think abstractly. Let’s digress for a moment here.

Logic games are all about abstraction. What does that mean? It means that by the time I reach the end of the game, I don’t even remember what the variables I’m working with represent anymore. Were they towns? Grocery stores? Alien invasions? It doesn’t matter. They are just letters that I am moving around. You are simply putting some game pieces (the free variables up on the left) into some spaces (the numbered slots that make up your base).

Once you strip away the irrelevant particulars, all of these games are exactly the same: you are ordering some pieces. The sooner you start looking past the distracting details and start looking at all these ordering games as just minor variations on the same game, the sooner these games will feel really, really easy. Don’t worry, I will remind you of this point frequently.

Now that we’ve got a sample base and the game pieces all written out, it’s time to learn to add some rules. Move on to the next lesson.