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LSAT
Course: LSAT > Unit 1
Lesson 3: Analytical Reasoning – Articles- Getting started with Analytical Reasoning
- How to approach ordering setups
- How to approach grouping setups
- How to approach mixed setups
- Given info: basic orientation | Quick guide
- Given info: could be true/false | Quick guide
- Given info: must/cannot be true/false | Quick guide
- New info: could be true/false | Quick guide
- New info: must/cannot be true/false | Quick guide
- Equivalent rule, min-max and completely determines | Quick guide
- Equivalent rule | Learn more
- Study plan for analytical reasoning | Getting more than 10 right
- How to use multiple scenarios in analytical reasoning setups
- Deductions in analytical reasoning | Introduction
- Deductions in analytical reasoning | Practice
- Diagram notation conventions for analytical reasoning setups
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New info: must/cannot be true/false | Quick guide
"Must be true" questions
The answer to a Must be true question is a statement that is always true, in any circumstance that is acceptable to the rules.
The wrong choices could be false—they don’t have to be true, because you can find at least one scenario in which the info in the choice isn’t true, but the scenario still works.
"Must be false" questions
The answer to a Must be false question is a statement that is always false—or impossible—in any circumstance that is acceptable to the rules. In other words, the answer breaks at least one of the rules when you incorporate the info from the choice into the setup.
The wrong choices could be true—they can be possible in at least one scenario.
Top Tip: Think of must be false as “impossible”, and could be true as “possible.”
Checklist for New info: Must be true/false questions
✓ Redraw the bare bones of your initial diagram
Since you are given new information here, a good method is to redraw the bare bones of your initial diagram (while keeping an eye on the other details from your initial diagram), so that you aren’t modifying your initial diagram with a condition that isn't going to extend to other questions about the setup.
✓ Incorporate the new condition in the new diagram
Usually it’ll be a condition you can draw right into the new diagram, but sometimes you won’t be able to, and it’ll be a rule that you need to write down—even though you’re not sure yet where those elements are going to go.
✓ Combine the new condition with your original rules
Any new deductions you can come up with in this step are likely to point you straight towards the answer.
✓ Use process of elimination
Check your new diagram and deductions—it’s possible that the answer is evident now. If not, eliminate choices that the new diagram and deductions rule out.
✓ Test any remaining choices
"Must be true" questions
Test the choices by trying to make the choices false. If you can make the statement in the choice false, and the scenario it produces is still acceptable, then you can eliminate that choice!
"Must be false" questions
Test the choices by trying to make the choices possible. If you can incorporate the info in the choice into the setup and make an acceptable scenario, then you can eliminate the choice, because it could be true!
Top Tip: If only two choices remain, and you feel confident in your work so far, you can just test one of them—if it accomplishes what you need (whether it’s a must be true or must be false) then it’s the answer! If it doesn’t accomplish what you need, then the other remaining choice is the answer.
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whats the difference between new info and given info(1 vote)
New info comes from the question at hand rather than the initial set of parameters. It's typically only used for that specific question.(3 votes)