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Course: LSAT (DEPRECATED) > Unit 1

Lesson 5: Analytical Reasoning – Worked examples

Mixed setup | Rule substitution | Worked example

Watch a demonstration of one way to approach a "Rule substitution" question on a mixed setup from the Analytical Reasoning section of the LSAT.

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Video transcript

- [Instructor] Before you watch this video, make sure to watch the overview video for this setup. That's where we notated the rules and made the deductions that you're gonna see me using here. So the question asks which one of the following, if substituted for the constraint that Hernandez must be interviewed in a segment that is earlier than any segment in which Fallon or Munson is interviewed, would have the same effect in determining the program segments in which the politicians are interviewed? This type of question can be challenging, and sometimes students opt to skip them entirely because they can often be time-consuming. We're looking for a rule in the choices that could replace rule number one and have the exact same effect. We'd see the same deductions, no more deductions, and no fewer deductions than what we originally got. So let's revisit rule number one. It tells us Hernandez must be interviewed in a segment that is earlier than any segment in which Fallon or Munson is interviewed. Now, let's evaluate the choices and see which one could replace this rule and have the exact same effect on the setup. A, Hernandez must be interviewed in a segment that is earlier than any segment in which Lewis or Munson is interviewed. This doesn't work because it gives us an entirely different deduction than what we originally had. We knew that Hernandez had to be on an earlier segment than Fallon or Munson, but this choice changes Fallon to Lewis. And it's not true that Hernandez has to be earlier than Lewis. For example, if you take a look at scenario two, Lewis could be in segment one and Hernandez could be later than Lewis in segment two. B, Hernandez must be interviewed in a segment that is earlier than any segment in which Fallon or Kim is interviewed. This is our answer. This rule has the same effect as rule one because we know that Munson and Kim are a pair based on rule two. So all this choice did was swap out Munson for Kim, which is totally fine since Munson and Kim always go together anyway. Let's check the remaining choices in case you had questions about them. C, Neither Fallon nor Munson can be interviewed in the first segment. This is a true deduction because we know that neither Fallon nor Munson can be in segment one. However, this choice doesn't replace rule number one because we've now lost the part about Hernandez being earlier than Fallon or Munson. And since we've lost deductions, this choice doesn't adequately replace rule number one. D, Fallon most be the sole politician interviewed in one of the program segments. Just like with choice C, this is one of our initial deductions, but it doesn't have the same effect as rule one because we've now completely lost the relationship between Hernandez and Fallon and Hernandez and Munson. E, Hernandez must be interviewed in the same segment as either Greer or Lewis. This isn't a good replacement for rule number one because in scenario two of our original setup, Hernandez could be alone in segment two while Greer and Lewis would be together in segment one. This choice would no longer allow for Hernandez to be alone, so it adds a deduction that wasn't originally true. So our answer is B.