Law School Discussion

Nine Years of Discussion
;

Author Topic: PT34 - June 2001 section IV #23 logic games  (Read 997 times)

silverapplejam

  • Jr. Member
  • **
  • Posts: 7
    • View Profile
    • Email
PT34 - June 2001 section IV #23 logic games
« on: August 08, 2010, 05:11:05 AM »
I am so confused about #23. In the condition part, it already tells us "if L is at Souderton, then both N and P are at Randsborough", then why in #23, the right answer (E) indicates that both N and P CANNOT be a pair at Rands? are they contradictive? appreciate your help! 

marcus-aurelius

  • Sr. Citizen
  • ****
  • Posts: 352
    • View Profile
Re: PT34 - June 2001 section IV #23 logic games
« Reply #1 on: August 08, 2010, 07:38:11 AM »
What is the entire question say?

Cambridge LSAT

  • Full Member
  • ***
  • Posts: 30
    • View Profile
    • Cambridge LSAT
    • Email
Re: PT34 - June 2001 section IV #23 logic games
« Reply #2 on: August 08, 2010, 01:53:25 PM »
Here are the rules:
1) JS → KR; KS → JR (contrapositive)
2) JR → OS; OR → JS (contrapositive)
3.1) LS → NR; NS → LR (contrapositive)
3.2) LS → PR; PS → LR (contrapositive)
4) NR → OR; OS → NS (contrapositive)
5.1) PR → KS; KR → PS (contrapositive)
5.2) PR → OS; OR → PS (contrapositive)

You can break up the third and fifth rules for easier tracking. Once you chain everything up, you should end up with something like the following:


It's easiest to create the first chain and then flip and negate everything to obtain the second chain. Because LS leads to LR in both cases, we can infer that L must be assigned to Randsborough. This is not a common inference for an In/Out Grouping game. To see why N and P cannot both be at Randsborough, start from one of the two being assigned there. In the first chain, PR leads to NS, and in the second chain, NR leads to PS.

silverapplejam

  • Jr. Member
  • **
  • Posts: 7
    • View Profile
    • Email
Re: PT34 - June 2001 section IV #23 logic games
« Reply #3 on: August 10, 2010, 10:24:24 AM »
it is funny when i realize that i've been set by the question maker at the beginning, now i see the true color of them.  i admit i fell in, thanks for the tip otherwise i will never get it how i fell.  it is logically impeccable but i just dont' like the way they make this game.  i hope they won't do it again, or they just do it on all games so i just grab the rule and don't have to pay attention to all the premises.  i guess being a lawyer you have to be this alert. 

EarlCat

  • Global Moderator
  • Sr. Citizen
  • ****
  • Posts: 2533
  • i'm in ur LSAT blowin' ur curve
    • AOL Instant Messenger - EarlCat78
    • View Profile
    • EarlDoesLSAT.com
Re: PT34 - June 2001 section IV #23 logic games
« Reply #4 on: August 14, 2010, 08:48:05 PM »
huh?