A question on must be true logic games .

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eric922

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Joined: Thu Nov 01, 2012 10:05 pm

A question on must be true logic games .

Let's say I have a Must be true question. If I just create a plausible hypothetical that works within the rules and I see an answer that matches something from my hypothetical should I simply pull the trigger on the answer that matches? After all, if it must be true then there is no need to test it, correct?

CardozoLaw09

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Joined: Sat Aug 28, 2010 1:58 pm

Re: A question on must be true logic games .

Only pull the trigger on that answer choice if there's nothing else that matches your hypo in the answer choices. Something that must be true will always be true no matter what hypo, but the danger in pulling the trigger as soon as you see something that matches your hypo is that it could just be a coincidence that your hypo matched one of the answer choices and that particular answer choice need not always be true but could be true.

If a question asks what must be true if M is in slot 5 and you do a hypo and with L in slot 3, and one of the answer choices is "L must be in 3" then only pick that answer if every other answer choices does not correspond to your hypo. Sometimes there will be two answer choices that match your hypo and then you'd need to do further analysis as to which one must always be true.

Pneumonia

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Re: A question on must be true logic games .

Although in the course of making one you might find a "MBT" the only thing a hypo proves is "can be true."
Usually 3/5 and sometimes 4/5 wrong answer choices on "must be true" are answers that "can be true" and are put there intentionally to trick you.

che3055

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Joined: Fri Nov 23, 2012 3:45 pm

Re: A question on must be true logic games .

Pneumonia wrote:Although in the course of making one you might find a "MBT" the only thing a hypo proves is "can be true."
Usually 3/5 and sometimes 4/5 wrong answer choices on "must be true" are answers that "can be true" and are put there intentionally to trick you.

Exactly. You can create a hypo where one of the answer choices is the case, but that doesn't prove that it MUST be the case.

For these questions, if I don't see something that jumps out at me right away about an answer choice, I negate each answer choice and build a hypo around that negation. For example, let's say an answer is "R must be 4th." I then to create a situation where R is somewhere other than 4th. If I can do that, that isn't the answer. If I cannot do that, that is the correct answer.

bp shinners

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Re: A question on must be true logic games .

This is where options and linked options come in handy, instead of just filling something in to see if it works. For these questions, most of the CBT (incorrect) answers will be players that are linked together and split two slots; you just don't know which one goes where. If you get those linked options in your hypo, you can quickly get rid of those ACs.

052220151

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Re: A question on must be true logic games .

If it is a universal 'must be true', the answer is normally an unstated inference, if you diagram well, this will take about 10 seconds to get the right answer.

If it is a hypothetical 'must be true' (i.e., if X is third, which of the following...), plug X into third, or whatever hypothetical information they gave you, and see how that reacts with the rules. Usually you don't have to fill out the hypo, and you shouldn't (because then you muddy the waters between 'can be true'). 9 times out of 10 these will be pretty easy because of some rule that says 'if Y isn't third, then Z is sixth'. So if X is third, y isn't third, so Z must be sixth.

Sorry for my lame example, I hope it helped.

Clearly

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Joined: Sat Feb 11, 2012 4:09 pm

Re: A question on must be true logic games .

The real trick with must be true and could be true: PRIOR WORK. If you do the questions in the right order, you should have at least one diagram for each "If" question, plus the acceptability question. If something "Must be true", it must line up in every one of these diagrams you've already done. Four out of five times you will already have the answer you are looking for literally sitting on your page. The single, number one most important 'tip' for logic games, is keep your work organized, and legible, be sure to very clearly mark failed hypotheticals, and get very good at referencing this valuable data.