LSAT 20, Game 2 Setup, Library Budget Cuts, LSATHacks

LG Game 2 Setup, by LSATHacks

Game Setup

This is an in-out grouping game, with two twists. First, only five of the eight variables are selected. Second, we need exactly two of M, L and R. That rule is key to the game. It’s so important that you simply have to memorize it. If you have L and M, you can’t have R. If you have R, you need L or M but not both. And so on. If you don’t remember this, the game is twice as hard, and much slower.

Memorizing key rules is an underappreciated part of logic games success. Few people do it, but it’s not really any harder than remembering a phone number for a few minutes. And it can get you into law school.

We can combine the rest of the rules. Start by drawing the first rule.

We can connect this with the second rule. If we have N then we don’t have S. The contrapositive is if we have S then we don’t have N. Likewise if we have R, we don’t have N. So we can draw it like this.

The third rule goes on its own. P leads to not L, L leads to not P. It’s worth thinking about how this works with the final rule. If we don’t have L we must have M and R.

The contrapositive of the larger diagram above is interesting. If we don’t have W we also don’t have one of S and G. That’s two missing out of eight, and we need five total.

We also are missing one of N and R. And we’re always missing one of L and P. That is four missing, if W is out. We don’t have enough.

Therefore, we can deduce that we always have to have W. There’s no way to get five variables in otherwise. Here’s the contrapositive diagram we can draw.

(We could have four from this diagram with S, R, L and M in)