Good question, Caroheavey, and one we have handled before (and which causes a ton of confusion, especially for students who are just starting to learn about conditional reasoning). I have moved your post to the thread where we discussed the setup of this game, specifically the rule you are asking about.
Basically, "only if" indicates a Necessary Condition, which goes to the right of your conditional arrow. The other condition in that relationship is the Sufficient Condition, which goes to the left of the arrow. So, "Lalitha performs third only if
Norton performs fifth" (emphasis added) means that N fifth is Necessary and L third is Sufficient, like so:
This means that any time you put L third, N has to be fifth, and anytime N is NOT fifth, L cannot be third. Be careful, though! N in fifth position does NOT require that L be in third position! That would be a Mistaken Reversal of the rule. They test that on question 8!
Let us know if you need further elaboration. If conditional reasoning is still not your strong suit, seek it out in whatever materials you are using, whether that is our Logical Reasoning Bible, the Accelerated Course book, or Lesson 2 in the Full Length course books, and practice, practice, practice. Good luck!
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
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