LSAT Prep Test 31 (June 2000) - Section 1 - Logic Game 2

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Prep Test Question Keywords: music, store, ten, types, cd's, new, used, jazz, opera, pop, rap, soul, on, sale

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Question Type Tags Responses Difficulty
PT31 S1 Q07
+LG
+InoAdv
A
B
C
D
E
-
•••Medium
PT31 S1 Q08
+LG
+InoAdv
A
B
C
D
E
-
•••Medium
PT31 S1 Q09
+LG
+InoAdv
A
B
C
D
E
-
•••••Hardest
PT31 S1 Q10
+LG
+InoAdv
A
B
C
D
E
-
•••••Hardest
PT31 S1 Q11
+LG
+InoAdv
A
B
C
D
E
-
•••Medium
PT31 S1 Q12
+LG
+InoAdv
A
B
C
D
E
-
••••Harder
PT31 S1 Q13
+LG
+InoAdv
A
B
C
D
E
-
•••••Hardest

If you had trouble with this game, you should practice the other Games that are similar to this one (listed below).  That way, you’ll learn to see how the Logic Games really are all the same. That’s how high scorers see them and that’s how you can improve your speed, accuracy, and score.

Start with the Games in the same set as this Game.  Then, work on the Games in the other sets.

The Difficult In/Out Games Set
PT31-Game2 | PT32-Game2 | PT49-Game3
_________________________

The Basic In/Out Games Set
PT33-Game2 | PT40-Game4 | PT45-Game3 | PT58-Game2

The Basic+ In/Out Games Set
PT34-Game4 | PT41-Game3

The Easy In/Out Games Set
PT24-Game1 | PT29-Game1 | PT36-Game1 | PT48-Game1 | PT54-Game1 | PT63-Game1

The Medium In/Out Games Set
PT20-Game2 | PT39-Game4 | PT47-Game2 | PT58-Game4 | PT59-Game3

Notes


PrepTest 31 - Question explanations


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37 Responses to “LSAT 31 – Section 1 – Game 2”

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  • saquib.najm

    Why is it better to not link up rules 1 and 3? How do you determine when it’s better to link up conditional chains and when to leave them on their own? Thanks a mill!

  • mrlsat180

    This video was gold. I think I just reached a new level in my skills in the games after watching this video.

  • dwschloss

    For question 10, rather than just trying all of them in a row, would it not make more sense to try to pare them down to the most likely first? So, for example, because ‘O’ doesn’t have any conditional rules, I would save it for the end and try answer choices D and E first (and probably save myself 2-3 minutes in the process).

    Is that kind of strategy advisable or could the same kind of strategy come back to bite you in the ass just as often as not?

    • J.Y. Ping

      Oh yeah, you definitely want to be strategic in your “brute forcing”.

      • co4ma8

        I did the same, but still took almost 15 minutes to finish the game (all correct). Any ideas on how to get through the questions quickly? I think I wasted a couple of minutes trying to link the conditionals at the set up as well. How do you know to not bother?

  • soupy1212

    Could premises 4 and 5 be written just as R ->/S ?

    • TackyTrackSuit

      You can, if you can also differentiate (R) as being Ru or Rn, then /Su and /Sn, rather than Ru and Rn > /Su and /Sn.

      Furthermore, the contrapositive is more than just S > /R; it is Su or Sn is sufficient for Ru and Rn.

      It you are incredibly adept at conditional logic to make that distinction, go ahead but for the majority of people, drawing out Ru or Rn > /Su and /Sn is more beneficial to see that relationship.

  • rbleal007

    Do you have a “rule of thumb” on in/out games when you put rules on the “master” game board? In LSAT 31, game 2, you put the first rule–(Used pop is on sale; new opera is not) on the game board. There’s no logically indicator here, so I assume that’s why you placed this rule on the game board as opposed to any others.

    • J.Y. Ping

      I don’t think that mattered too much right?

      You should put in a “switch” item if it takes up the last slot. That’s because it’ll help you to see that the other remaining items must file into the other group.

      Like if X/Y takes up the last IN slot and we still have W and Z to place, then we know that W and Z must go into the OUT group.

  • dlkzwicker-1

    Question 7 – cannot see connection between answer choice C and premise 3.
    Premise 3 refers to Jazz and new pop but the choices do not include Jazz.
    This is a tough one!

    • J.Y. Ping

      Yeah you have to be solid with your conditional logic and this lesson: http://7sage.com/lesson/conditional-rules-trigger-v-irrelevant

    • drivestainless

      Take the contrapositive of premise 3 and you will see that if Pop (new) is not on sale, then either of the Jazz must be.

  • Llaima01

    I agree with priyamsingh1988. The same thing happened to me. I got the question right eventually but I wasted precious time checking the other 4 answers. Thoughts?
    Thank you!

  • priyamsingh1988

    I have a question about question 8. “At least one type of pop is not on sale” implies that both types COULD BE not on sale. But rule #1 explicitly says used pop IS on sale, meaning that it CANNOT BE not on sale. This would mean I’d have to test A-D and once I rule them out reluctantly pick E. What am I missing here?

    • J.Y. Ping

      For why (E) must be true, consider the following: Say you and your friend are at the movies. You go see Indie film and your friend goes to see an IMAX blockbuster. I say “at least one of you saw an Indie film”. Is that a true statement?

      If you’re not sure how you can get directly to (E) without checking (A) – (D), then maybe watch the video again. We make an inference.

  • Mike Ross

    This is weird to notice but did anyone else realize that this is the question that reese witherspoon does in legally blonde hahahah okay im done.

  • jory1burks

    Lol, so the reason this game was so hard for me, was because I read the first statement as if used pop is one sale; new opera is not. Just cleared up all my problems by just reading this statement correctly.

  • Midriff

    Still confused on #9 a bit. How come you can put PN in either the for sale or not for sale row?

    • J.Y. Ping

      Because Pn has freedom to be in or out. Do you see why it can do that?

      • Midriff

        ya i see it. U can just fail the suffecient and makes the rule irrelevant. Therefore u can throw it out. I just didn’t realize you have the power do that without the question saying so.

  • K

    Correct me if I am wrong guys but I combined everything when I did this game and had this diagram:

    /J(u)&/J(n) —> P(n) —> S(u)&S(n) —> /R(u) or /R(n)

    here’s what it looks like drawn out:

    http://imgur.com/u0rSaAS

    *disregard the “or” in inference #4… I meant to write “and” but wrote “or” hahaha

    I was able to answer all the Q’s correctly.

  • Sydney Sun

    For question #9 does Used pop not count as one of the types of CD’s on sale?

    • Monsura Sirajee

      It doesn’t count because the question asks for the min # of new CDs (i made the same mistake!)

  • Caitlin Klein

    For question 7, why is C wrong? Premise 3 doesn’t seem to have anything to do with it.

    • J.Y. Ping

      It does. Do you see that (C) triggers the sufficient condition in Premise 3?

      • Monsura Sirajee

        I don’t see it :( Can you clarify further?

        • Monsura Sirajee

          Actually, I think I do see it. Is the problem that the list is not complete? Pn should also be in the on sale section.

  • TC

    Question #10 (LSAT PrepTest 31/Logic Games)

    Rather than filling out the in/out box for each answer choice, I did the following…

    Answer choices (A), (B) and (C) all have opera included in them. I know used opera is a floater, so it can be in or out at any time.
    (A) also states neither type of rap is on sale. I know this CAN BE true because of Rule 3 (If both types of jazz are on sale then no rap is on sale). So, (A) can be eliminated.

    Answer choice (B) states neither type of jazz is in. I know this CAN be true because of Rule 4, “if neither type of jazz is on sale, then new pop is. So, I eliminated (B).

    Answer choice (C), same thing. Again, I have already taken care of used opera. Rule 5 states “if either type of rap is on sale, then no soul is.” This tells me it is possible to have both types of soul CD’s out at the same time, so (B) can now be eliminated.
    I identified Answer choice D as the correct answer by combining Rule 1 (If new pop, then all soul) with Rule 4 (if neither jazz then new pop). When you do, it looks like this: /jn and /juàpnàsn and su). I immediately saw that jazz and soul had an either/or relationship (when each genre contained both new and used) and therefore, one genre had to been in. They COULD NOT both be out.

    Answer choice (E) can easily be ruled out be referring to Rule 3, “If both types of jazz are on sale, then no rap is. This is a “not both” relationship, so both could be out.

    I arrived at the answer choice in fifteen seconds or so. Is the aforementioned method an acceptable way to arrive at the answer choice? In other words, although I selected the right answer, is it possible that handling the problem in this fashion would have caused me to overlook something in a similar LSAT problem?

    • Brian LSAT

      I don’t think you can use the reasoning you have above. Someone please correct me if I am wrong. Just because you are given A –> B as a rule, this does not mean that A is actually possible, and therefore doesn’t imply that B is actually possible. Seems like very dangerous logic to me.

      “Answer choice (B) states neither type of jazz is in. I know this CAN be true because of Rule 4, “if neither type of jazz is on sale, then new pop is. So, I eliminated (B).”

      Well, how do you know both Jazz can not be on sale if you don’t prove it out? Just because it appears in a rule does not mean it’s actually possible. For the LSAT maybe you can get away with this most of the time, but it’s risky.

      A good example is game 34-4 where you have separate rules that when chained, leads to a contradiction. For example, you get L–>N and L–>/N when you chain the rules. According to your logic, L can be in because it appears in a rule. But when you take all the rules into account, you actually infer that L can NEVER be in even though it appears in the sufficient condition in two separate rules.

      For #10, I looked at the answers and noticed that it was putting two entire types of CDs out in a MBF question, meaning that I need to look for a scenario where you have an OR relationships between two entire CDs. Looking at rule 1 + rule 3 shows an OR relationship between /Jn & /Ju –> Sn & Su, which is our classic OR rule—both can’t be out. Quickly, we can see this in answer D.