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Course: LSAT > Unit 1
Lesson 5: Analytical Reasoning – Worked examples- Ordering setup | Overview | Rules and deductions
- Ordering setup | Given info–basic 1 | Worked example
- Ordering setup | Given info–basic 2 | Worked example
- Ordering setup | Given info–could be true | Worked example
- Ordering setup | Given info–cannot be true 1 | Worked example
- Ordering setup | Given info–cannot be true 2 | Worked example
- Ordering setup | Given info–must be true | Worked example
- Ordering setup | New info–could be true 1 | Worked example
- Ordering setup | New info–could be true 2 | Worked example
- Ordering setup | New info–could be true 3 | Worked example
- Ordering setup | Completely determines | Worked example
- Ordering setup | New info-must be true | Worked example
- Grouping setup | Overview | Rules and deductions
- Grouping setup | Given info–basic | Worked example
- Grouping setup | Given info–could be true | Worked example
- Grouping setup | Given info–must be false | Worked example
- Grouping setup | Given info–must be true 1 | Worked example
- Grouping setup | Given info–must be true 2 | Worked example
- Grouping setup | New info–could be true 1 | Worked example
- Grouping setup | New info–could be true 2 | Worked example
- Grouping setup | New info–must be true | Worked example
- Grouping setup | "Completely determines" | Worked example
- Mixed setup | Overview | Rules and deductions
- Mixed setup | Given info–basic | Worked example
- Mixed setup | Given info–could be true 1 | Worked example
- Mixed setup | Given info–could be true 2 | Worked example
- Mixed setup | Given info–must be true | Worked example
- Mixed setup | Given info–cannot be true | Worked example
- Mixed setup | New info–could be true | Worked example
- Mixed setup | New info–must be true 1 | Worked example
- Mixed setup | New info–must be true 2 | Worked example
- Mixed setup | Rule substitution | Worked example
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Mixed setup | Given info–must be true | Worked example
Watch a demonstration of one way to approach a "Given info: must be true" question on a mixed setup from the Analytical Reasoning section of the LSAT.
Want to join the conversation?
I don’t see how the deduction was made here for scenario 1, either in this or one of the previous questions.
In scenario 1, F has to be in either segment 2 or segment 4 but in this worked example we’ve somehow determined it can only be segment 2. Why? What makes 1: H/G 2: L 3: M/K 4: F illegitimate, for instance?(35 votes)- That was a possible scenario deduced earlier. I think they're a little unclear there. What they are saying is that you know that one will work, and you can eliminate answers based on that. you can eliminate C, because it proves that Greer and one other politician being interviewed in the same segment isn't true in that scenario.(2 votes)
- when was it deduced that F had to be in segment 2 in scenario 1? This wasn't told in any working out previously, and F could also be in segment 4 in scenario 1 (as was told in the previous question)(22 votes)
- correct. still though, F has to be the sole interviewer in spots 2, 3, or 4 (never paired with H)(1 vote)
- What rule states that Fallon cant be in segment 4 in the first scenario?(16 votes)
- where is the new information coming from in the start of the video? It kind of confused me.(12 votes)
- For scenario 1) F could also be in 4... You could have 2 as F/G/L and 4 as F/G/L but given this, I don't see any reason why scenario 2) doesn't have the corresponding information filled out.(10 votes)
- There is not enough information to arrive at a conclusion that Fallon MUST be in segment 2 in the first set up.... but for the purposes of the question, this fact does not matter... as whether or not Fallon is in segment 2 or 4, the answer remains that it must be true that Fallon is alone.(9 votes)
When will this video be back up? It's not generating via Youtube.(3 votes)- This issue has been repaired.(1 vote)
Video transcript
- [Instructor] Before
you watch this video, make sure to watch the overview
video for this same set up because that's where we notated the rules and made the deductions that you're going to see me using
here. This question asks which one of the following must be true of one of the program segments? So, we need to identify what must be true given the set up rules.
Since we are not given any further context to work
with, we're going to have to evaluate each of the choices in turn against what we know to be true. (A) is that Fallon is the
sole politician interviewed Does this have to be true?
Well, if it's true in both scenarios, then it must be
true. So let's take a look. In scenario one, we deduced in our set up that Fallon has to be in segment two and that Fallon is alone. In
scenario two, we know that Fallon can't be first and
has to be second or third and both segment two and segment three feature only one politician.
So this choice must be true. Fallon will always be alone
in an interview segment. On test day, you can either
move on at this point or glance over the rest of the choices in order to confirm your answer. It largely depends on you
and how your timing is going and your confidence.
So let's take a look at the rest of the choices.
(B) says that Greer is the sole politician interviewed.
Well, this could be false. We see in scenario one
that Greer could be paired with Hernandez in segment one. So this doesn't have to be true. (C) Greer and exactly one
of the other politicians are interviewed. No, this
could be false as well, because in scenario one
Greer could be alone in segment four. That would leave Lewis in segment one which is just fine. (D) Hernandez and exactly
one of the other politicians are interviewed. Well, this
is true in scenario one but it could be false in scenario two. Hernandez could be
interviewed in segment two which would put Fallon in segment three and leave Greer and Lewis in segment one. Since this is acceptable, then
it doesn't have to be true that Hernandez is paired
with someone else. (E) states that Lewis
and exactly one of the other politicians are interviewed. And this could also be false,
because of scenario one Lewis could be alone in segment four. So (A) is our answer,
because it must be true, while all of the other choices
we looked at could be false.