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- Mon Sep 01, 2014 12:27 pm
#84911
Setup and Rule Diagram Explanation
This is a Grouping/Linear Combination game.
This game features two elements: the group of four runners that will compete (Grouping), and the order of the races in which they run (Linear).
The first two rules address Linear aspects of the game, with the first rule creating a block if Q runs in the track meet (and a Q Not Law on the fourth race):
Note that because there are only five available runners for four races, T must always run in one of the races. Otherwise, via the contrapositive, Q could not run in a race, leaving only three runners for four races.
The second rule creates two Not Laws for S (shown with the Not Law from the first rule):
The third and fourth rules address both Grouping and Linear aspects of the game. The two rules combine to create a double-arrow rule:
Thus, if U is not in the track meet, then R runs second, and if R runs in the second race, U cannot be in the track meet. This is a very powerful rule, because if R runs in the second race, then U cannot run in the track meet, meaning that S, Q, and T must all run in the track meet. And, because Q and T form a block, they must run in the third and fourth races, leaving S to run in the first race:
The contrapositives of the third and fourth rules also create a double-arrow:
Thus, if U runs in the track meet, then R cannot run second, and if R runs in any other race aside from the second race, U must be in the track meet.
This is a Grouping/Linear Combination game.
This game features two elements: the group of four runners that will compete (Grouping), and the order of the races in which they run (Linear).
The first two rules address Linear aspects of the game, with the first rule creating a block if Q runs in the track meet (and a Q Not Law on the fourth race):
Note that because there are only five available runners for four races, T must always run in one of the races. Otherwise, via the contrapositive, Q could not run in a race, leaving only three runners for four races.
The second rule creates two Not Laws for S (shown with the Not Law from the first rule):
The third and fourth rules address both Grouping and Linear aspects of the game. The two rules combine to create a double-arrow rule:
Thus, if U is not in the track meet, then R runs second, and if R runs in the second race, U cannot be in the track meet. This is a very powerful rule, because if R runs in the second race, then U cannot run in the track meet, meaning that S, Q, and T must all run in the track meet. And, because Q and T form a block, they must run in the third and fourth races, leaving S to run in the first race:
The contrapositives of the third and fourth rules also create a double-arrow:
Thus, if U runs in the track meet, then R cannot run second, and if R runs in any other race aside from the second race, U must be in the track meet.
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Dave Killoran
PowerScore Test Preparation
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PowerScore Test Preparation
Follow me on X/Twitter at http://twitter.com/DaveKilloran
My LSAT Articles: http://blog.powerscore.com/lsat/author/dave-killoran
PowerScore Podcast: http://www.powerscore.com/lsat/podcast/
Not R2 (one or the other or both appear)
r2, and r2 
r2.