Preptest 9 game 3

Posts: 33
Joined: Tue Dec 18, 2007 10:11 pm

Preptest 9 game 3

Postby winnatech » Wed Jun 16, 2010 1:41 pm

I am a bit confused as to how to diagram one of the statements, "Whoever partners R in dance 2 must partner S in dance 3." I initially diagrammed this as

X2, R2 --> X3, S3 (X being one of the K, L, M) but as I started doing the problems, I started to see that the person dancing with S in dance 3 has to be the same person dancing with R in dance 2, making it X3, S3 --> X2, R2. Was I diagramming the "Whoever...must..." wrong?


Posts: 8
Joined: Sat Dec 19, 2009 11:44 pm

Re: Preptest 9 game 3

Postby imnion » Wed Jun 16, 2010 3:22 pm

IIRC this game, the easiest way to diagram that rule is just to draw an arrow from R2 to S3. There's only something like 3 templates in this game, so drawing them out is the easiest way to diagram the rules.

Posts: 33
Joined: Tue Dec 18, 2007 10:11 pm

Re: Preptest 9 game 3

Postby winnatech » Thu Jun 17, 2010 12:40 am

I see. So for the line "Whoever partners R in dance 2 must partner S in dance 3." the correct diagramming is just X2, R2 --> X3, S3 (X being one of the K, L, M), not a double arrow right? Just wanted to make sure I am diagramming this rule correctly.


User avatar
Posts: 438
Joined: Thu May 20, 2010 4:18 am

Re: Preptest 9 game 3

Postby zworykin » Thu Jun 17, 2010 1:22 am

I'm confused--are you asking if X2,R2=>X3,S3 logically implies X3,S3=>X2,R2?

Yes, it has to go both ways. If you find that K2R2 occurs, then K3S3 must also occur; if you find that L3S3 occurs, then L2R2 must also occur.

I haven't read any bibles/taken any courses so I'm not sure if you're trying to follow some diagramming patern set forth by someone else, but in my own system (which is basically "do whatever feels right for the situation") I would draw it as a 3x3 grid with 1/2/3 down the Y axis and R/S/T across the top. Then my rules would be:

K=S1 or S2 => K=/=S3
each pair only once

So, I wouldn't be using arrows or anything like that. I could put a K in the box for S3 and cross it off, since it's not possible. We can deduce that since each pair can only occur once, whoever dances with R2 and S3 must dance with T1. So make that rule T1=R2=S3. And since K=/=S3, then K also cannot be R2 or T1.

There are only 4 scenarios that work in this game. I ended up diagramming each of them in the course of answering the questions, and strongly considered simply diagramming them before even starting since the possibilities were so limited. I've found that when there are so few ways to work the game out, it's often worthwhile to simply draw them all from the start.

Trying to diagram this game any other way just wouldn't make sense to me. But hey, whatever works for you is what you should stick to.

(Side note: I actually really liked this game. Very quick and elegant, I thought.)

Cambridge LSAT
Posts: 257
Joined: Mon Aug 24, 2009 3:26 pm

Re: Preptest 9 game 3

Postby Cambridge LSAT » Thu Jun 17, 2010 1:43 am

It is a double arrow, because the two positions are inextricably linked. Because the partners cannot be repeated, each boy must partner with each girl during the course of the three dances, and there is also a double arrow between T1 and R2. As imnion and zworykin mentioned, you can use the two sets of dual options to create four solutions.
Image (LinkRemoved)

Return to “LSAT Prep and Discussion Forum”

Who is online

Users browsing this forum: tlsadmin8, Vianco and 2 guests