Main content
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
© 2024 Khan AcademyTerms of usePrivacy PolicyCookie Notice
Mixed setup | Overview | Rules and deductions
Watch a demonstration of how to approach a mixed setup on the analytical reasoning section of the LSAT.
Want to join the conversation?
- At8:38(looking at Scenario 1), why can't Hernandez be in segment 2 and Fallon go in segment 4? This would create a scenario where you'd have G and L in segment 1, H in 2, M and K in 3, and F in 4.(29 votes)
- The scenario you described is definitely possible it's just not the only solution to the problem so she didn't fully fill it out for scenario 1. It is also possible that H could be in segment 1 with G or L in section 2.
We just don't have enough information at this time to fully solve scenario 1.(2 votes)
- Same as the other guys. In Scenario 1 she's saying a rule is there that isn't,8:31.(9 votes)
- H not being able to go into segment 3 isn't explicitly given as a rule but can be deduced by the rules given. We know that H is followed by F and M (rule 1) and that M is tied to K (rule 2), so H must have three empty segments following it for F, M, and K to go into. This isn't possible if we put H in segment 3.(1 vote)
- Why only 2 politicians allowed in segment 1?(3 votes)
- I believe that only 2 are allowed in 1 because the first segment has to be greater than the second segment, and if the first segment had 3 it would only allow for segments 2-4 to have 1. Which would not allow for the MK rule to work. Please let me know if this is correct, but I believe it is. Good luck.(8 votes)
- At8:51the diagram is incorrect. The person in the video falsely puts H in 1 to precede F and MK, but H could just as easily be in 2 and F in 4. She simply jumps to an utter non sequitur.(5 votes)
- Why can't there more than one person in 2 if there are only 2 people in 1?(2 votes)
- "At least one of the politicians will be interviewed in each segment, and none will be interviewed in more than one segment."
It doesn't specify that each politician is interviewed at least once. Isn't it possible then to have 1-2 politicians not be interviewed? Why is it assumed otherwise? This trips me up when making concrete deductions.
For example, to satisfy Rule 3, couldn't a potential setup could be 2:1:1:1? Do we assume all values in a setup/range are used once?(2 votes)- "A radio station is planning a program in which a total of six politicians -[list]- will be interviewed."
six politicians will be interviewed, so no it is not possible to have 1-2 politicians not be interviewed. This is the first information given in the introduction.(1 vote)
- In understanding the 3rd rule (05:47), can we not also say that there could be 3 spaces for speakers in the first segment and the rest have only one speaker? It says "more of" so that is why I am thinking this is so.(1 vote)
- I found the answer. Someone else posted that the MK rule still needs to be applied and this would not obey the MK being in the first segment.(1 vote)
Video transcript
- [Instructor] We're now
going to work through a mixed setup together, so
make sure that you've already worked through ordering
setups and grouping setups before you tackle this one,
since we're going to be combining the two tasks
into one setup here. So let's start by examining
the introductory passage to understand what
we're being asked to do. The passage tells us a radio
station is planning a program in which a total of six politicians, Fallon, Greer, Hernandez, Kim, Lewis and Munson,
will be interviewed. The program will consist
of exactly four segments. At least one of the politicians will be interviewed in each segment, and none will be interviewed
in more than one segment. The following constraints apply. Before we look at the rules, let's understand what's going on and then build a rough sketch to reflect what we understand the situation to be. So first, our players are six politicians, so it's a pretty good idea
to take inventory of them by writing a list of their initials. We have Fallon, Greer, Hernandez, Kim, Lewis, and Munson. Next, we can ask
ourselves what we're doing with these politicians, and in this setup, we're grouping them into four segments. Since the order of the segments matters, given that this is one single program that's broken into four segments, that means that this is a mixed setup. If we had had four politicians and four segments, one
right after another, then this would actually have
been a classic ordering setup. But in this case, we have six
politicians for four segments, so that means that some of them will have to be grouped together. Now, for a mixed setup
that involves grouping and ordering like this,
it can be really helpful to look at the ordering part first, and then try to figure out how
the grouping aspect fits in. So, knowing that we have four segments, we can draw a blank for each
segment and number them. All right, now let's
think about the grouping. With six politicians and four segments, how many blanks do we
still have left to place? Two. What does that mean for our possibilities? Well, either one segment
gets three politicians and the rest of the segments
get one politician each, or two segments get two politicians each, and then two segments
get one politician each. So we're looking at
three, one, one, and one, in some kind of order, or two, two, one, and one, and again, we wouldn't know the order. So now we know that the
maximum number of politicians interviewed in any given
segment has to be three, and we can mark that if we're
worried that we'll forget. So for our diagram, if we were to find out that a segment had more
than one politician, we could draw additional blanks underneath the corresponding
segment number, and that gives us a really
good starting framework in terms of the numbers,
and that we can hope that the rules will give us information that allows us to deduce
even more about the numbers. At this point we have a basic diagram, so let's go ahead and
move on to the rules. Our first rule is an ordering rule, and it tells us that Hernandez must be interviewed in a segment that is earlier than any segment in which Fallon or Munson is interviewed. Well, what does this mean? It means that Hernandez is an
earlier segment than Fallon, and that Hernandez is an
earlier segment than Munson. So we can make a note of this
so we don't forget, like this. It's important to note that we don't know how Munson and Fallon
relate to each other. Munson and Fallon could
be on the same day, or they could be on separate days, with either Munson earlier than Fallon, or Fallon earlier than Munson. Even with these uncertainties, we can start making deductions right away. So, think: Who can't be in the fourth
segment based on this rule? Hernandez can't be in the fourth segment, since Hernandez has to
be in an earlier segment than at least two people. Be careful though. Hernandez could be in the third segment if Fallon and Munson are
together in the fourth segment. So this is all we know so far about where Hernandez can't go. What about Fallon and Munson? We know that they can't
be in the first segment, again, because Hernandez has
to be in an earlier segment than both of them, which
would be impossible if either Fallon or Munson were first. Our second rule is a grouping rule, and it tells us that Kim and Munson must be interviewed in the
same segment as each other. Normally we would note
down a separate rule that Kim and Munson are a pair, but here we can actually save
a bit of time by noticing that we just learned about
Munson in the first rule. So we can actually combine rule number two with rule number one like this. And our group of politicians
is getting bigger, which means we know more. In which segment can
Kim not be interviewed? In segment one, because Kim has to be
sometime later than Hernandez. We now know of three politicians who can't be in segment one. The third and final rule is
that more of the politicians must be interviewed in the first segment than in the second segment. This is huge, it tells us a lot. We can deduce that the first segment must have at least two politicians, and maybe it even has three. And if the first segment
had three politicians, then all of the other segments would have to have one politician each. So that means we know
that the only segment that even could have three
politicians is the first one, since the numbers combinations are either two, two, one, one, or
three, one, one, one. We also know that if the first segment had two politicians and not three, then the second segment would
still have only one politician so we can deduce that the second segment must have only one politician in any case, and we can mark this
in any number of ways. I like closing off the
column with double lines to remind myself that no more blanks can ever be placed there. You can choose whatever
works best for you. Let's see what else we can deduce by revisiting some of the rules, now that we have some
stronger number guidelines. We learned that Munson
and Kim are together, and that they're sometime after Hernandez. Well, we just deduced that there can be only one politician
interviewed in segment two. This tells us that the
Munson and Kim pair, which we know can't be
in the first segment, must be together at some point in the third or fourth segment. So, it's no longer a possibility that there are three politicians
in the first segment. We know that there must
be only two politicians in segment one, and either two politicians in segment three or in segment four. That means that we're limited
to only two scenarios. So if you'd like, we can build them out in order to see everything more clearly. (virtual marker squeaks) In scenario one, we'll put Munson and Kim in segment three, and in scenario two, we'll put Munson and Kim in scenario four. These are the only two places that the Munson and Kim pair can go, which is why it's a good idea for us to build out these two scenarios. Now we can see a lot more. What else? Since we now know that no segment can include three politicians, we can look at our grouping
here and see that Fallon and the Munson-Kim pair can't be together. Why is this important? Well, since they have
to be on separate days, that means that there
are at least two segments after Hernandez is interviewed, so now we know that Hernandez can't be interviewed on day three. To recap, we just set up a mixed task that involves ordering and grouping. We took the numbers guidelines that we were given in the
last rule and made sure to get all of the information from
it that we possibly could, and that allowed us to understand
that only two scenarios involving Munson and Kim are possible. We took our time and looked at
the implications of each rule making sure to included deductions about where elements can't go,
not just where they can go. So we are in a really strong position to move to the questions
with this initial diagram that we're gonna use for support.