Diagram

[bergstressers]

This looked easy at first -but I couldn't diagram in enough constraints to get the last four questions..! Is the conditional R/F -> G>R ? I got lost in the overlapping conditionals - V & S exactly 2 apart and S next to F and H>V... help!

[ManhattanPrepLSAT2]

I've attached a diagram for this game --

The big inference to be made up front is that there must be dance songs played 1,3,5 and 7.

The unless constraint is a tough one to translate --

"F must be played immediately after R, unless G is played earlier than R."

One tip for when you are stuck trying to correctly understand a tough conditional -- try to start by just thinking of the one thing you know MUST BE TRUE.

One thing that must be true, according to what we are told, is that if G is not played before R (that is, if R is played before G), F must be immediately after R. We know that with certainty, so we can notate it:

R - G -> RF

Now we can take the contrapositive -

- RF - > G - R.

Now for the questions -

#19 is an orientation q - we can eliminate answers based on constraints:
1st constraint eliminates A
2nd constraint eliminates D
3rd eliminates C
5th eliminates B

Therefore, (E) is correct.

#20 is (D) - we can get this off our diagram.

#21 - we know the fourth song is a ballad, so it can be F, G, or H.
That eliminates all answers but (A), the correct answer.

#22 - we know the first song is a dance song, so it must be R, S, V, or X.

That eliminates (D) and (E).

We also know V has to come after H, so we can eliminate (C).

Down to (A) and (B), it's a bit tougher, and we have to try some trial and error.

For (A) If R is first, F must be second, S is third, V is fifth. H would have to be fourth. That all seems fine.

For (B) If S is first, F is second, and V is third. This would violate the rule that H must come before V.

Therefore, (A) is the only possibility left standing.

#23 .

If S is third, V is fifth. Notice, we went through some of this work on the previous q -- for evaluating (A) for #22, we got to...

RFSHV as one way to fill the first 5 slots. In this case, we'd have G and X left -- since we need a ballad in #6, G would have to go there.

Note that the work we did above was just one hypothetical involving S being third, but notice that this question stem subtly tells us there is only one possibility for what can go sixth here. If we know G can go sixth, and we know only one element can go sixth, then we can know G MUST go sixth.

(A) is correct.

#24 If the seventh song is R, the fifth song must be one of the three remaining dance songs -- S, V, or X.

That gets us down to (D) or (E). For (D), there seems no reason why we couldn't put V fifth.

For (E), if we put X fifth, S and V would have to fill slots 1 and 3 -- there is no way they could do so without violating the rule that H must be before V. Therefore (E) is not a possibility, and

(D) is correct.

Hope that was helpful. I've certainly left some spaces in the explanation for you to fill in -- please follow up if you have additional questions!

[stacksdoe]

Mike Kim,
You work for Manhattan prep?
I always feel like the explanations don't go deeper then surface level….

WIth this disc jockey game, you are absolutely correct with the "big inferences" regarding the dance songs. Furthermore, with a little more analysis it becomes apparent that V and S can not go into slot 1, consequently only R and X and be slotted in the first space.

Albeit process of elimination is great on many of these questions, questions 21 and 22 can be efficiently answered by just scanning for the correct answer choice.
Number 21 inquires what variable can go into the fourth slot, well as Mike pointed out only FG or H can go there, look for one of them and your done.

With number 22, if you made the initial inference that only R or X can go into slot one, then look for one or the other and your set. If you didn't make this initial inference, you should arrive at answer (A) or (B) by process of elimination and then do as Mike points out.

WIth number 23, it's between A and B, quickly produce a mini sketch and place S in slot 3 and V in slot 5-since the latter can not be placed in slot 1- and you'l easily see that G must be placed in slot 6.

As with the last questions, you should be able to quickly arrive at two answer choices, here, namely (D) and (E). Two hypotheticals, one to prove and the other to disprove should suffice.

Hope this helps!

[tommywallach]

Hey Stacks,

Seems like you misunderstand the way the forum is organized. This post is JUST for the diagram (not any individual questions). Mike just included those to give a general sense of how the diagram could help. Individual questions are discussed on individual threads within the posting of the game itself. If you don't see any, it's only because no student has asked a question about any of those questions yet.

-t

[stacksdoe]

oops, thanks Tommy !

[JacquelineR76]

I picked E on question 19 and got it wrong.