LG Game 4 Question 23 Explanation, by LSATHacks
Everyone hates rule substitution questions. But they’re not that hard if you consider that the only way to replace a rule is to use the other rules.
Looking at the full effect of all the rules helps you decide how to replace the rule. For instance, look at the setup diagrams for this game:
W is pretty restricted. They can only go first or second. Who can go in front of W?
- Not K and L. Rule 3 says they go after.
- Not T. It goes after K.
- Not Y, because Z needs to go before Y.
(Don’t worry, I explain the third bullet below)
So only Z can go before W. A is CORRECT.
The final bullet point is the hardest to understand, so I made a diagram to show what happens if we put Y before W:
Putting Z and Y before W pushes W third, and this pushes L fourth, which isn’t recorded. So that violates the rule from the setup that L must be recorded. You get the same result with K.
(K and L can’t go sixth. See the setup for the full explanation. But basically, you either have KT in 5th and 6th, or L in 5th, and K somewhere earlier, because it goes before T)
For this question (PT 78, S2, 23) I understood that W had to be first or second so I choice answer D… I don’t understand why A is the answer if the other rules make it so that Z is the only other singer that can go before W… if it’s implied, why does it need to be articulated?
>if it’s implied, why does it need to be articulated?
Because we removed the rule that made it so! If you remove the rule about W being before the recorded auditions, then it is no longer true that only Z can go before Z. K could go before Z, for example, because no rule forbids it. That’s why D is wrong. W could be second, and recorded K could go first.
Whereas A achieves the goal of rule 3 by other means. In the regular game, an implication is that only Z can go before W. This is because of rule 3. So now, without rule 3, saying on Z can go beforehand achieves the same result.
Why doesn’t answer choice D work?
I am wondering why D is not valid in this situation.