#2 - Local, Must Be True

[Administrator]

Please post your questions below!

[klaq15]

I tried this several times and always came down to B and D. Ultimately I guessed it right, but...

When I placed P (printers), my permanent pieces would be "_ _ S P _ H _". (S can't be after P because then we would get "L H _ P S _ T" and if T is seventh then R would have to be first. And since L must come before H, they're fighting for the spot and it's a no-go.)

Then that "_ _ S P _ H _" configuration can play out as "T R S P L H M" or "R M S P L H T" or whatever, but speakers are still third (answer B) and headphones are still sixth (answer D).

What am I missing here? Thanks.

[ava17]

Hi, I made the inference that S was in 3, but doesn't that also mean it must be true that H is in 6? How can both of those answers be correct?

[Adam Tyson]

Hey guys, good questions, and great job figuring out that S must be 3rd. There's actually a global inference in play that S can never be 5th, which most people would probably miss in the diagramming stage, but that's an issue for another thread (the setup and diagram thread for this question). Here, if you tried to put S 5th, you would find that you could not place H anywhere and still comply with the requirement that L is before H and also that only T or R can be first.

Here's where you are both making a mistake, and it's an easy one to make. H can go 6th OR 7th! The rule is that at least two weeks must separate S and H, not that exactly two weeks must do so! That means another viable solution to this game would place H 7th, which would force T to be first, and the rest of the variables (L, R, and the random variable M) could go in any of the remaining spaces, like so:

T _ S P _ _ H

Read carefully, and pay special attention to words and phrases like "at least" and "at most" and "exactly"! Misinterpreting those leads to bad assumptions and problems with questions like this one.

Also, don't do more work than needed before checking your answers to a Must Be True question. Once you placed P 4th, and you saw that S could not be 5th, the very next inference you probably made was that S had to be 3rd. Don't take another step before checking the answer choices! Is "S is 3rd" an option? It is! Select it and move on to the next question, with confidence. Don't waste time filling out more of the diagram at that point - only do that if the first inference you made isn't an option. That's another way to become more efficient on games, giving you time to spend on the more challenging questions.