Hey there brebre234, one thing you can do to test these ideas is to try them out in a diagram. Go ahead and put F in the 5th position, and see what happens, or try putting I in the 2nd spot and see if you can make it work. In both cases, you'll find that it isn't possible, as either will force you to break one of the rules.
Without doing that work of testing things out, though, you can still get there by noting that F must have at least two things after it - G, which is immediately after it, and also I, which has to be somewhere after G. If F has at least those two things after it, then it cannot go last and it also cannot go second-to-last. Likewise, I must have at least two things before it - G, which is somewhere before it, and F which is immediately before G. With two things before I, it simply cannot fit at first OR at second.
Both rules must be applied together - you cannot do them in isolation. Putting I 2nd might look okay if you apply only the G
I rule, but you still need to have an FG block. Putting F 5th might seem okay if you just do it as part of the FG block, but you still need to comply with the rule that G is somewhere before I!
If that explanation still isn't clicking for you, do as I suggested at the beginning and test each of them out. Let us know if that doesn't clear things up!
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
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