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LOGIC GAMES BIBLE 2017: page 548, #15

LSAT Apprentice
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Help! On page 548 of the above listed book, I do not understand how B is the correct answer for number 15. Is C incorrect because it fails to place P in a consecutive position? And is the same issue of "consecutive" applicable to Answer E? Please let me know. Thank you.
Adam Tyson
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Hey there, Hope, let me see if I can help with that!

Your approach to this question should be to first eliminate any loser answers, ones that you can see right away are impossible. For example, you might have tried some "what if" scenarios while doing your original diagram using the conditional rule about O on Thursday and come up with these two possibilities when O is on Thursday:


You should be able to eliminate answer A quickly, because when O is Thursday and P is Monday, there is no division other than S that is toured on two consecutive days. After that, you may have to do a little testing to see what happens with your remaining answer choices.

Testing answer B, we start by doing what the answer tells us to do: put P on Tuesday and S on Wednesday:


Now, S has to be part of an SS block, per the original rules, so we get this:


The rules also tell us that O cannot be Monday, and S only goes those two times, so that means Monday has to be P:


We have to get an O in there somewhere, and Friday is all that's left, so there we have it!:


This solution works, complies with all the original rules, and complies with the local restriction in the question (another consecutive pair besides the SS block, which in this case is the PP block on Monday and Tuesday). We have a winner!

Now, let's try answer C, starting by doing what the answer tells us to do, which is place O on Tuesday and P on Friday:


There's only room for the SS block at Wednesday/Thursday, so let's put it there:


Now, to comply with the question's local restriction, we need another block of two divisions consecutively. The only way to do that is to put an O on Monday. But the second rule prohibits that! We cannot comply with all the rules, including the local restriction posed by the question and the requirements of answer C, and get a workable solution. That's why it's not the credited response to this question. It's not that there are not two consecutive Ps (although there are not), but that there is no consecutive pair other than the SS block.

Now let's try the same thing with answer E, since you asked! The answer says to put S on Wednesday and P on Friday, like so:


We cannot put an O on Monday, but we have to place one somewhere. What if we put it on Tuesday? That would force the SS block to be on Wednesday and Thursday:


Nope, no way to get a second block of two consecutive divisions. Okay, let's try that O on Thursday instead, with the SS block on Tuesday/Wednesday:


We still can't get another block of two consecutive days of the same division! E won't work no matter which way you try to solve it. It''s out!

On these local questions, be sure to comply with the local restriction posed by the question, AND to remain compliant with all the original rules (unless instructed otherwise, as in a "rule substitution" question). When in doubt, draw it out!

I hope that helps!
Adam M. Tyson
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