Limited Option Games? Forum

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Anaconda

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Limited Option Games?

Post by Anaconda » Mon Jul 26, 2010 3:33 pm

So PT 30 Game 3 (The car wash involving- Vinquetta, Jebrohn, etc) really messed me up because I didn't realize that if you set up two scenarios, there are limited options and the questions answers all fall into place. Without realizing that, the game is impossible without a 2 scenario diagram.

I'm really disappointed with myself that I simply froze and couldn't finish the game. I could have simply made 4 hypotheticals allocating T to all its possible slots (which would have taken some time but would have given my the right answers), but I couldn't even think of that! Really embarrassing.

My question is, when do diagram multiple scenarios when diagramming, and most importantly, does anyone know of any games similar to the infamous car wash game? This game is going to give me nightmares because it's a -6 if you can't figure it out and a -0/-1 if you diagram it correctly by realizing it has limited options.

Also, would any books have good explanations of advanced sequencing games? IMO the LGB has an inadequate chapter on it.

Audio Technica Guy

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Re: Limited Option Games?

Post by Audio Technica Guy » Mon Jul 26, 2010 6:33 pm

Anaconda wrote:So PT 30 Game 3 (The car wash involving- Vinquetta, Jebrohn, etc) really messed me up because I didn't realize that if you set up two scenarios, there are limited options and the questions answers all fall into place. Without realizing that, the game is impossible without a 2 scenario diagram.

I'm really disappointed with myself that I simply froze and couldn't finish the game. I could have simply made 4 hypotheticals allocating T to all its possible slots (which would have taken some time but would have given my the right answers), but I couldn't even think of that! Really embarrassing.

My question is, when do diagram multiple scenarios when diagramming, and most importantly, does anyone know of any games similar to the infamous car wash game? This game is going to give me nightmares because it's a -6 if you can't figure it out and a -0/-1 if you diagram it correctly by realizing it has limited options.

Also, would any books have good explanations of advanced sequencing games? IMO the LGB has an inadequate chapter on it.
Pohl children game PT 39, Section 1, starting with question 12 immediately comes to mind.

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AverageTutoring

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Re: Limited Option Games?

Post by AverageTutoring » Wed Jul 28, 2010 11:47 pm

I thought I would write up a review on this game because I believe there is a better way to go about it then exhausting all options up front.

Main Diagram

Image

Immediate deductions

We know O, M, F and T need to come some time after V. In other words, 4 people need to come after V. Consequently V must go first because there are only 5 available slots.

With no clear restrictions on T it seems plausible that T can fit anywhere between O, M and F as long as he comes after V. Can we map out every scenario? Yes. But this is not necessary to complete this game. While there are limited possibilities we don’t need to exhaust all possible hypotheticals to be quick and accurate.

However, it is important to establish the relationship between O and M and their relative spots and washes. No matter where T goes, O will be in either slot 2 or 3 and M will either be in 3 or 4.

This is important to note because the rule that states the car before M must have a regular wash plays into the fact that slots 2 and 3 will have the same kind of wash. If M is in slot 3 then slot 2 must have a regular wash. However, if M is in slot 4 then slot 3 must have a regular wash and by the rules that means slot 2 must have a regular wash. So no matter where M goes, slots 2 and 3 must be regular washes!

Updated Main Diagram

Image

Let's move onto questions.

Question 11

This is a simple rule violation question. We’ll apply the rules and see where we end up.

A: Immediately we note O goes first which cannot be the case. Wrong
B: Correct
C: O comes after M which is not possible. Wrong
D: V cannot have a Super. Wrong
E: There must be AT LEAST 1 super but there is none here. Wrong

Question 12: If V does not receive a premium wash, which one of the following must be true.

Image

Inferences

If V does not receive a premium wash then V must receive a regular wash. This tells us that both V and O receive a regular wash. Outside of that, there are a few possible combinations that can happen. So let’s see what MUST be true.

A: Done. V and O must both have regular washes.
B: Possibly.
C: Possibly.
D: Possibly.
E: Possibly.

Question 13: If the last 2 cars receive the same wash as each other, what could be true?

Image

Inferences

If the last 2 washes are the same then we know they cannot be Regular washes because if they are both Regular washes then Slots 2, 3, 4 and 5 are all Regulars. This simply cannot happen because we need AT LEAST 1 Super (which by the rules cannot be Slot 1). By the same token, we know they can’t both receive a Premium wash because there is EXACTLY 1 Premium wash. So they definitely must be Supers. And if 4 and 5 are Supers, that means 1 must be a Premium (since there must be 1 premium and 2/3 are always regulars).

By extension, if 4 is a Super then it cannot be M because M receives a regular wash. But since our initial inferences revealed that M can go in either 3 or 4 and now it cannot go in 4, then it must go in 3. Which also means O goes in 2 because O must come before M.

Updated Diagram for Question 13

Image

A: Does not happen.
B: Could be true.
C: Does not happen.
D: Does not happen.
E: Does not happen.

Question 14: What Must be True

Image

For this question we will simply check the answer choices against our diagram.

A: Does not have to be true.
B: Does not have to be true.
C: Does not have to be true.
D: Does not have to be true.
E: Boom goes the dynamite. Car 2 does need to have a Regular wash.

Question 15: What is an accurate list of those cars that MUST receive a regular wash.

Image

Clearly any answer choices with V in it is incorrect. By question 13 we know that both T and F DO NOT have to have regular washes. Further we deduced up front that O must go in slots 2/3 which require a regular wash and per the rules M must have a regular wash. So the answer becomes M/O.

Answer choice B is correct.

Since question 16 does not deal with the use of the existing hypotheticals I won’t go in detail. The point of this was to show you that we really don’t need to exhaust all possibilities in this game. We simply need to exploit the rules as given on a per question basis.

What you ultimately find more efficient is up to you. I just wanted to show you that this game can be done as effectively, if not more so (in my opinion), without exhausting all possibilities up front.

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