Logic Game - PT 34, Section 4, #19-24 Forum

[schand]

I can't get this game, someone please help! Thank you!!

[Mattalones]

I can't get this game, someone please help! Thank you!!

Can you post it? I don't have it on hand and would love to look at it

[schand]

I can't get this game, someone please help! Thank you!!

I just PMed you the question. Thank you!!

[Mattalones]

Before I start ranting on about what to do, can you check to see if I got the answers right? I could be way off.

19) B
20) A
21) C
22) D
23) D
24) B

[FreeGuy]

http://www.top-law-schools.com/forums/v ... 5#p2368792

Your answers for 22 and 23 are incorrect

[Mattalones]

http://www.top-law-schools.com/forums/v ... 5#p2368792

Your answers for 22 and 23 are incorrect

Thanks...

23 was a typo; I got (E).
22 I legit got wrong.

So, what I actually got:

19) B
20) A
21) C
22) D
23) E
24) B

Which ones gave you trouble and which ones did you get right?

[schand]

I didn't get 21, 23, and 24. How did you diagram this? I usually have a tough time diagramming long conditional reasoning games. I'm not really sure what is the optimal way to do this. Do you write down the contrapositve after each criteria? I read a post once that said that they put together all the conditional statements together first, then write down the contrapositive. Any advice?

[schand]

http://www.top-law-schools.com/forums/v ... 5#p2368792

Your answers for 22 and 23 are incorrect

I just looked over the explanation. That is a sneaky deduction! I would never have thought to pay attention to that.

[r6_philly]

http://www.top-law-schools.com/forums/v ... 5#p2368792

Your answers for 22 and 23 are incorrect

I just looked over the explanation. That is a sneaky deduction! I would never have thought to pay attention to that.

I solved all the questions without needing that deduction about L.

22:
if N O are not at the same clinic.
So 1. Ns Or or 2. Os Nr. but rule #4 is Nr -> Or, so 2 is incorrect. Then it must be Ns Or
because Or, rule number 2 dictate that J must be s. So 22 is A

23:
you have try every one. But the last one is Nr + Pr
if Pr, per rule #5 ditake that Ks + Os. because Os, then N must be Ns. so P and N can't be both at r. Answer E.

[r6_philly]

I didn't get 21, 23, and 24. How did you diagram this? I usually have a tough time diagramming long conditional reasoning games. I'm not really sure what is the optimal way to do this. Do you write down the contrapositve after each criteria? I read a post once that said that they put together all the conditional statements together first, then write down the contrapositive. Any advice?

when I write rules I wrote:
Js -> Kr
Jr -> Os
Ls -> Nr + Pr
Nr -> Or
Pr -> Ks + Os

To solver problem, I put 2 columns, like
s | r
-----
J K (rule 1)

like that . I don't write down the contrapositive because I am CS major and I am used to think that way (so I can consider it without writie it out), but it may help you to write them out. so you can write the rules as
Js -> Kr ==> Ks -> Jr
Jr -> Os ==> Or -> Js
you can even go one more ==> Or -> Ks || Kr -> Os

[Mattalones]

Sweet! Well, I am able to help you with all of them now. That was a fun game. Let me know if I can answer any more questions, but I think that I'll go through everything below:
________________________________________________________________________________________________
Rules:

1* Js->Kr
2* Jr->Os
3* Ls->Nr & Pr
4* Nr->Or
5* Pr->Ks & Os
________________________________________________________________________________________________
Setup:

I just put them together and everything (except #22) fell into place because if one of the doctors is not in "s," then he's in"r."

Or->Js->Kr->Ps->Lr
Jr->Os->Ns->Lr

... I thought this was key (it shows that "Ls" can never happen):
Ls->(Nr & Pr)->(Ks & Os)->Ns
(If "Ls" were to happen, then it would imply that "Ns & Nr," but "N" is a doctor and can only be in one hospital at once; thus, "Ls" is impossible and every hypo you make must have Dr. L in Hospital S).

Also very important (from rule #4): Since "Nr->Or" implies "Os->Ns," the only way for these two doctors to be in different hospital is "Ns & Or" (helpful for Question #22, which I see now ... stupid oversight on my part).
________________________________________________________________________________________________
Question:
19) Givens are in normal font, and what follows from the rules are in bold font.

a) (Js means Kr, but we already have Ks and K can only be in one place at a time ... No go!)

R: K
S: J, K, O

b) (Js means Kr and Lr, and all variables are taken up w/o breaking rules ... Seems good. TITCR.)

R: K, L
S: J, N, O, P

c) (Os means Lr, but we already have Ls ... two places at once again)

R: L
S: K, L, O

d) (Pr means Ks, but, since N & O are the only things in hospital S, K is already in hospital R ... No go!)

R: J, K, L, P
S: N, O

e) (Jr means Os, but we already have Or ... No go!)

R: J, K, L, O
S: N, P

20) "If Pr, then what must be true?" (Givens in normal font, deductions in bold font)

R: P, J ... This proves that (A) is right
S: K, O

21) What is the Min Dr. @ Hospital S? (I did this my putting all the Drs in Hospital S and then moving them to stay w/in the rules)

If you look at all of the rules, there are only two - rules 2 and 5 - that force anything into Hospital S. They force Os & Ks; nothing else gets forced there, so there must be at least two Drs in Hospital S by the following hypo:

R: J, N, L, P
S: O, K ... This proves that (C) is the correct answer

22) From rule #4, the only way for N and O to be at different hospitals is as follows (givens in normal font and deductions in bold):
R: O L
S: N P

The only two unaccounted for variables are J and K, and, since rule #2 says "Jr->Os," and we already have Or, that means we must have Js as follows:
R: O L
S: N P, J ...This proves that (A) is the correct answer.

23) Which Dr cannot be in hospital R?
Rule #4 says "Nr->Or," and rule #5 implies "Or->Ps." Putting these rules together means "Nr->Ps," or "Nr->~Pr." So, We can never have (Nr & Pr) ... This proves that (E) is the correct answer.

24) If Ks, then what must be true? (below has givens in regular font and deductions in bold)
R: J
S: K, O, N ...this proves that (B) is the correct answer.
_________________________________________________________________________________________________

Whew!!! I love conditional games. I don't know why I didn't get #22. O well. I figured it out, and I hope that this was helpful.

[Mattalones]

Bummer! I thought someone would reply at least once to a full explanation ...

[schand]

No, this is great Mattalones! Thank you so much for the explanation. I just haven't gotten a chance yet to look closely at it. There is another conditional reasoning game I am having trouble with if you're interested

[Mattalones]

No, this is great Mattalones! Thank you so much for the explanation. I just haven't gotten a chance yet to look closely at it. There is another conditional reasoning game I am having trouble with if you're interested

I'm down ... No work right now and I'm kind of nerdy to begin with ... Bring it on

[abbas123]

that's a great explanation - thanks!

[Mattalones]

No problem ... it was actually pretty fun. ... What ever happened to that other game that was mentioned on this thread. I want to do another one (obviously have time to kills )