#7 - Local, Cannot Be True

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Complete Question Explanation
(The complete setup for this game can be found here: lsat/viewtopic.php?t=6800)

The correct answer choice is (A)

If W is the first piece on the CD, then the third rule would be immediately satisfied as W would be earlier than both R and T. Both options about the sequence of R, T, and S presented by the second rule would still be viable, which—when combined with the first rule—produce the following two local diagrams:

PT73_Game_#1_#7_diagram 1.png

Since we need to identify what cannot be true, four of the answer choices could be true in at least one of these two diagrams; the remaining answer choice would not be true in either diagram. Some of the answer choices could also be eliminated using using previously made local diagrams in which W is first, as discussed below.

Answer choice (A): This is the correct answer choice. The first possibility outlined above would force T to be second:

PT73_Game_#1_#7_diagram 2.png

The second possibility would force T to be no earlier than 4:

PT73_Game_#1_#7_diagram 3.png

In neither solution can T be third, proving that answer choice (A) is correct.

Using templates, you can easily see that W can be first only in Template 1A and 2A. In neither template can T be placed third.

Answer choice (B): This answer choice could be true, because V could be 3 using the second local diagram above, or Template 2A:

PT73_Game_#1_#7_diagram 4.png

This answer choice can also be eliminated using the local diagram from Question #5, answer choice (E), in which we established that W and S could be the first and the second piece, respectively. In that diagram, V can clearly be third:

PT73_Game_#1_#7_diagram 5.png

Answer choice (C): This answer choice is incorrect, because S could be 4 using the first local diagram above, or Template 1A:

PT73_Game_#1_#7_diagram 6.png

This answer choice can also be eliminated using the local diagram from Question #4, in which W was inferred to be the first piece. In that diagram, S can clearly be fourth:

PT73_Game_#1_#7_diagram 7.png

Answer choice (D): This answer choice is incorrect, because V could be fourth using either of the local diagrams outlined above. This is also shown in Templates 1A and 2A:

PT73_Game_#1_#7_diagram 8.png

This answer choice can also be eliminated using the local diagram from Question #4, in which W was inferred to be the first piece. In that diagram, V can clearly be fourth:

PT73_Game_#1_#7_diagram 9.png

Answer choice (E): This answer choice is incorrect, because T could be last using the second local diagram above, or Template 2A:

PT73_Game_#1_#7_diagram 10.png

This answer choice can also be eliminated using the local diagram from Question #5, answer choice (E), in which we established that W and S could be the first and the second piece, respectively. In that diagram, T can clearly be last:

PT73_Game_#1_#7_diagram 11.png

Question #7 is perhaps the most difficult question in the first game. This difficulty stems, in part, from the fact that the local condition results in multiple possible sequences about the placement of the remaining four variables. Another problem is the nature of the question stem itself, as the process of elimination requires the identification of four answer choices that could be true, potentially resulting in the creation of four local diagrams. A Templates-based approach could speed up this process tremendously, as would your ability to reference prior work. This is why it is imperative not to erase any of your local diagrams: you never know when you might need them again!