Setup and Rule Diagrams

[Adam Tyson]

Sorry about that, slettec! This thread predates a change we made in our full length course books earlier this year. Until recently, this WAS game 4 in Lesson 11! Now, because of recent trends in the actual tests, we decided to swap this one out for a pattern game. Here's a link to the explanation for that game:

lsat/viewforum.php?f=82

[slettec]

Thank you for the timely response, really appreciate it. That happened to be the one "killer game" I couldn't wrap my head around so it was really getting me haha

[eronquillo12]

Hi- this is not the killer logic game listed in the course book. Could you please update with June 2014 Logic game question 19-23 today?

[Adam Tyson]

eronquillo - see the link I provided in my previous post on this thread. That links to a description of the June 2014 game that is now in that lesson.

[T.B.Justin]

The contra positive of the 3rd rule; is this a correct understanding of wording it.

If either type of rap is on sale, either type of jazz is not on sale.

And, contra positive for the 4th rule:

If new pop is not on sale, either type of jazz is on sale.

[Dave Killoran]

The contra positive of the 3rd rule; is this a correct understanding of wording it.

If either type of rap is on sale, either type of jazz is not on sale.

And, contra positive for the 4th rule:

If new pop is not on sale, either type of jazz is on sale.

Hi TB,

Yes, those are correct! I might word it slightly differently just to be extra clear under the speed/pressure of the test, but the ultimate meaning is the same:

• Contrapositive of 3rd rule: "If either type of rap is on sale, at least one type of jazz is not on sale."
  
  
  Contrapositive of 4th rule: "If new pop is not on sale, at least one type of jazz is on sale."

Thanks!

[T.B.Justin]

Just for further clarification of my pre-phrasing with these conditional rules:

For the combined second and fourth rule, If no jazz is on sale, new pop is on sale, both soul's are on sale. For the contra positive, if at least one soul is not on sale, new pop is not on sale, at least one jazz is on sale.

Side note: I had it worded; with "and" separating the second and third condition but that can be confusing as it could be considered one condition. Is there a better way to phrase this?

[Brook Miscoski]

Justin, you are actually combining the 1st rule as well as the 2d and 4th rule:

1. Pu, -Ou (always)
2. PnPu SnSu
3. -Jn-Ju Pn

Since Pu is a constant, -Jn-Ju Pn(Pu_ constant) SnSu
And it follows from the above rules only that -Sn or -Su (or missing both) -Pn (Pu constant) Jn or Ju (or have both)

Using "and" is fine, or showing it the way I did above is fine.

[ashahab1309]

Hi there!

Okay, a small bit of confusion: for the inference where R--> ~S(NU) and ~S --> P(N) are linked together, how does that work? Why do we not diagram that first condition contrapositive as ~S(NU) --> ~P(N)?

[KelseyWoods]

Hi ashahab1309!

I'll answer your 2nd question 1st: The reason that we've diagrammed the contrapositive of that first statement with a S instead of a SNU is because if you're missing either new soul or old soul, you cannot have new pop. SNU would indicate that you are missing both new soul and old soul. S indicates that you are missing at least one soul CD.

Now to your 1st question: If you are missing both new soul and old soul (as in the last rule), then you are clearly missing at least one soul CD (because you're actually missing both!), which means we can connect those two conditional statements together. It might help to think of it as SNU S.

Hope this helps!

Best,
Kelsey