LSAT Preptest 61 Logic Games Explanations

Time on second attempt: 5:45

See “repeating games” at bottom of section

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I found this to be a medium-to-easy game. It’s a grouping game. One important point is that the order of the cars doesn’t matter: there’s no difference between car one and car two. They’re interchangeable.

I found this to be a rules based game. You might be able to make upfront scenarios, but I think there are many of them, too many to be practical. So, here are the rules:

It is also worth noting that each car needs at least two workers, so you can draw a diagram like this: 

On this game, it’s crucial to pay attention to who is restricted, and who is free. Faith is relatively free, and therefore important. She can drive both Hannah and Juan. So any scenario that doesn’t make Faith the driver is very restricted.

All six variables are covered in this setup. Every worker is affected by at least one rule.

When you’re placing people in the game, you should focus most of all on driver relationships. Often, placing one driver will force you to make more placements. 

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Repeating Games

I’ve written elsewhere about the benefits of repeating games, to solidify your intuition for deductions. Note that the purpose of repeating games is to prove the answers right, so it doesn’t matter if you remember the right answer.

I repeated this game about three days after I first saw it, by which time I had forgotten the answers. I’ve written how long it took me on the second attempt. That time, or a couple minutes above it, is roughly the standard you should be aspiring to – a lot of people take 8-9 minutes on a repeat attempt, get everything right, and pat themselves on the back. But that’s too slow. The faster you go when repeating, the faster you’ll learn to go the first time you see a game.

(I say “a couple minutes above” my time because, after years of teaching the LSAT, I’m really, really fast. You should be almost as fast as me, but you don’t exactly need to match my pace to score -0.)

Time on second attempt: 5:45

The setup section explains how to build this diagram.

Main Diagram

Rules

For acceptable order questions, go through the rules and use them to eliminate answers one by one.

Rule 1 eliminates D. Hannah needs Faith or Gus as a driver.

Rule 2 eliminates B and E. Faith or Kenneth must drive Juan.

Rule 3 eliminates C. Gus and Lisa must be in the same car.

A is CORRECT. It violates no rules.

This question asks who cannot be the driver. You should think about the answers based on who is the most useful driver:

• Faith is the most useful. She can meet both rules 1 and 2, by driving Hannah and Juan.
• Kenneth and Gus are the second most useful drivers. Each of them can fulfill one rule.
• Hannah, Juan and Lisa aren’t useful as drivers: they don’t fulfill any rules.

So the right answer will likely:

1. Not have Faith.
2. Have one of Hannah, Juan and Lisa.

That’s answer E, which is CORRECT. Why doesn’t E work? Because Faith and Gus aren’t driving, so there is no one to drive Hannah.

You don’t need to try the rest once you are sure about E. All you need to have done is looked at them, and decided they were unlikely. (Because, for example, A-C have Faith.)

This question makes Lisa drive a car. As we saw in question 2, that means Faith is going to have to drive the other car. That’s the only way to get both Hannah and Juan their proper drivers. We can draw this:

I also placed Gus with Lisa, to satisfy rule 3. K is hovering to the right of the diagram to show that K could go with either group.

Since this is a “could be true” question, the right answer will almost certainly include Kenneth, since only Kenneth is flexible. 

And this is the case: A is CORRECT. 

This question makes Faith not the driver. That makes this scenario hard. We can conclude two things:

• Gus will have to drive Hannah. (And Lisa will also have to be in the same car) (Rules 1 and 3)
• Kenneth will have to drive the other car, with Juan. (Rule 2)

Ordinarily, either group could with Faith in car one. But, the group with Gus has three people, whereas this question says Faith only has two other people. So that means Kenneth and Juan will have to go with Faith. We get the following diagram:

C is CORRECT. 

General “cannot be true” questions are hard. But, you can use past scenarios to disprove answers. If something worked on a past question, then it can’t be the answer.

This scenario from question 3 eliminates A:

Another way to eliminate answers is to ask if they are potentially fulfilling a rule, or not. E.g.:

B makes Hannah “not the driver”. This helps fulfill rules 1, which says Hannah is driven by Faith or Gus. (If Hannah was the driver, she obviously couldn’t be driven by someone else.)

C makes Juan “not the driver”. This helps fulfill rule 2, which says that Juan must be driven by Kenneth or Faith.

D, on the other hand, makes things harder, because Kenneth is normally a possible driver. Instead, D makes Kenneth unable to drive. Let’s see if we can make D work:

I made Faith the driver of the other car, and placed Hannah and Juan with Faith. This fulfills rules 1 and 2.

However, we still have to place Gus and Lisa together in a car (rule 3). This is impossible, as we have one space to fill in Kenneth’s car, and one in Faith’s. (And only GL are left)

So, D is CORRECT.

What about E? This diagram proves that it can work:

And if you think about, all E does is force us to place Gus in the car Lisa is in – which fulfills rule 3. We can then make Faith the driver in the other car, fulfilling rules 1 and 2.

Time on second attempt: 4:00 min.

See “repeating games” at bottom of section

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I found this to be an easy game personally, but that’s because I have a lot of experience with sequencing games. If you found this hard, good news: Sequencing games are by far the most learnable game type. Just do and redo them until every step is second nature, and you’ll get them down.

Here, you can make two diagrams:

The first diagram combines rules 1 and 2. The second diagram draws rule 3.

P is the only artifact not on the first diagram. So you could combine these two situations and make a combined diagram like this:

But, I think this is misleading. It really gives the impression that P is in front of F, when that is not the case (there is no line connecting them).

Instead, I preferred to recognize that P only had two possibilities, and visualize P moving ahead of or after N and H in both diagrams, as the situation calls for.

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Repeating Games

I’ve written elsewhere about the benefits of repeating games, to solidify your intuition for deductions. Note that the purpose of repeating games is to prove the answers right, so it doesn’t matter if you remember the right answer.

I repeated this game about three days after I first saw it, by which time I had forgotten the answers. I’ve written how long it took me on the second attempt. That time, or a couple minutes above it, is roughly the standard you should be aspiring to – a lot of people take 8-9 minutes on a repeat attempt, get everything right, and pat themselves on the back. But that’s too slow. The faster you go when repeating, the faster you’ll learn to go the first time you see a game.

(I say “a couple minutes above” my time because, after years of teaching the LSAT, I’m really, really fast. You should be almost as fast as me, but you don’t exactly need to match my pace to score -0.)

Time on second attempt: 4:00 min.

The setup section explains how to build this diagram.

Main Diagram

For acceptable order questions, go through the rules and use them to eliminate answers one by one.

Rule 1 eliminates D. The figurine has to be before both the jar and the headdress. 

Rule 2 eliminates B and E. The tureen has to be after both the necklace and the jar.

Rule 3 eliminates C. The plaque can’t be between the jar and the headdress.

A is CORRECT. It violates no rules.

Figuring out who can be first is a fundamental skill on sequecing games. To see who can be first, count those who have no other variables in front of them (with a line.)

Here’s the diagram again:

diagram 1

Both F and N could be first in this diagram. Also, P isn’t on this diagram, and could be first.

So, C is CORRECT.

This question asks who can’t be fourth. If someone is fourth, they must have three people before them, and two people after them.

So, look for people who are either at the very start, or end of the diagram. That would be F and T.

A is CORRECT. F can’t go fourth. F has H, J and T after them, so F can go third at latest.

What about T? T could go fourth if both H and P went after T, like this:

T doesn’t need to be after H: there are no lines connecting T and H.

If F is third, then H, J and T must come afterwards. That fills all spots after F:

Next, we need to place P and N. Since P is before H, that means we also need to put P before N (rule 3):

C is CORRECT. N must be second.

This question asks how many people can be second if P is first. The only people who can be second, are those that have no one else before them. So, let’s look at the main diagram: 

F and N have nobody placed in front of them. So either F or N could go second: B is CORRECT. 

Rule substitution questions seem hard, but what you must remember is that there aren’t that many ways to achieve an effect. To do this type of question, you should figure out the full effects of the rule. We’re trying to replace the rule that “The necklace and the jar are both older than the tureen”. 

But, by looking at the main diagram, we can see that there are other effects. Here is the main diagram again:

So it’s not just N and J that must be before H; it’s also F.

What about the others? Both H and P could either be before or after T.

So, look for an answer that shows awareness of these facts. D is CORRECT. It says that only H and P could go after T. That therefore forces J and N before T, even without the rule.

All of the wrong answers are wrong because they:

1. Forbid things that should be allowed, or
2. Allow things that should be forbidden.

The substituted rules must create scenarios that obey all other rules. This is a helpful thing to keep in mind in order to eliminate wrong answers.

• A: This contradicts the rules. T is supposed be after F.
• B: This doesn’t mention the jar, so this rule allows J to come after H.
• C: This rule allows both J and N to go after T!
• E: This says nothing about where J and N are placed. So they could both go after T.

So, A forbids something that should be allowed, and B, C and E allow things that should be forbidden.

The “if and only if” rules are especially poor candidates. You generally can’t replace an ordering rule with an “if and only if” rule.

Time on second attempt: 9:15

See “repeating games” at bottom of section. Note that I made an error on question 17 which slowed me down. I got it right, but it took time to spot the error. Errors happen in LG, which is why a buffer of extra time is a good goal to aim for, even once you reach the point of getting most questions right.

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This is a fairly simple game, but nonetheless difficult. The rules are easy to understand yet somehow a bit difficult to apply.

Here are the basic rules. The first diagram is just the main board, with rule 2 underneath – S can’t be 2nd or 4th:

I didn’t draw them for U and R, but note that if you have any difficulty visualizing contrapositives, you should also draw the contrapositives for the final rule. If you ever hesitate about them, then this is essential to prevent mistakes. But, at an advanced level this isn’t necessary.

About the only thing you should do in advance is think about who is easy to place, and who is hard:

• S is hard: it can only go first or third.
• R and U are hard: they both can have big effects
• Q is hard: When placed, it forms a block with T as QT 
• T is easy. Placing T alone doesn’t make anything else happen, and T can be placed anywhere.

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Repeating Games

I’ve written elsewhere about the benefits of repeating games, to solidify your intuition for deductions. Note that the purpose of repeating games is to prove the answers right, so it doesn’t matter if you remember the right answer.

I repeated this game about three days after I first saw it, by which time I had forgotten the answers. I’ve written how long it took me on the second attempt. That time, or a couple minutes above it, is roughly the standard you should be aspiring to – a lot of people take 8-9 minutes on a repeat attempt, get everything right, and pat themselves on the back. But that’s too slow. The faster you go when repeating, the faster you’ll learn to go the first time you see a game.

(I say “a couple minutes above” my time because, after years of teaching the LSAT, I’m really, really fast. You should be almost as fast as me, but you don’t exactly need to match my pace to score -0.)

Time on second attempt:

The setup section explains how to build this diagram.

Main Diagram

For acceptable order questions, go through the rules and use them to eliminate answers one by one.

Rule 1 eliminates C. If Q runs, then Q must be directly before T.

Rule 2 eliminates B. Smith can’t run second or fourth.

Rule 3 eliminates E. If U is not running, then R must run second.

Rule 4 eliminates A. If R is second, U can’t run.

D is CORRECT. It violates no rules.

This question asks who has to run. This game is quite restricted: four out of five runners must run. So, if one runner is out, that means every other runner must be in.

A lot of the runners have restrictions that may be incompatible. So, in order to make valid placements, we want to keep the people with fewer restriction in. In fact, the right answer is probably the runner with the least restrictions.

T is easiest to place. Placing them doesn’t cause anything else to happen. So, T therefore might have to be in (because they’re easy to work with: things might be too difficult without them).

Let’s test to see if T is really essential. If we don’t have T, then we must have everyone else: Q, R, S, U.

Right away we can see this doesn’t work. If we have Q, we need T. So Q, R, S and U isn’t a possible combination.

D is CORRECT.

This question asks how to fully determine the order. This means that the answer we pick must cause a chain reaction. To figure out which answer might do that, look at the rules, and see which ones causes the most things to happen.

I’d say it’s rule 4: placing R second eliminates U. That does two things:

• We know R is second.
• We can’t have U, so instead we have QT, R and S.

Let’s try drawing that:

So, R is second. Next we must place the biggest block, QT:

Finally, there’s only one space left for S, 1st:

So that proves that placing R second determines everything. B is CORRECT.

For “cannot be true” questions, you should look for answers which have particularly restricted variables. You can also “soft eliminate” answers that have easy-to-place variables. (see note at end)

T is easy to place. It has no restrictions, except one: if Q is in, then T goes right after Q, like this: QT

So, any answer with T probably doesn’t involve a contradiction. The only way to make one would be to say something like “Q is 2nd and T is 4th”, and that’s too obvious. You can have T in without Q, of course (which is why E works).

So, this means that C-E are unlikely candidates. We should instead look at A and B.

A says to put R immediately before S. That’s hard. S can’t go 2nd or 4th. And if S is 1st, then obviously R can’t go ahead of S.

So we have to put S 3rd, and R 2nd. Next, look for additional deductions. For example, if R is second, we can’t place U (rule 4). 

That leaves only QT (rule 1). But, if RS are in 2 and 3, then QT can’t be placed. They need two consecutive open spaces:

So, A is CORRECT.

But what about B, we didn’t eliminate that. B places S directly before Q. That means we must place T after Q (rule 1). SQT take up three spaces. We can’t place S second (rule 2), so we get this diagram:

We just have to fill 4th. We can place U 4th, so B is an allowable scenario:

Soft Elimination: This is when you conclude that an answer probably isn’t right. You’re not eliminating it, but you are checking other answers first. If you find the right answer, you can move on without 100% disproving the “soft eliminated” answers. 

This question places U first. And since U is in, that means R can’t go second (rule 4). You should draw that:

So both S and R can’t go second. Nor can U, since they’re first. So, who can go second? Q or T. Let’s try both scenarios. This one has Q second:

Rule 1 says T comes after Q, so T is 3rd. Only R and S are left to place. But, rule 2 says S can’t be 4th. So, R must be:

In the next scenario, T is second. That means Q can’t be in, because Q has to be directly in front of T (rule 1). So we get this diagram:

Since Q is out, only R and S are left to place.

But S can’t go fourth. So R must also go fourth in this scenario:

E is CORRECT. In both scenarios R is fourth.

This question places Q and S, and asks how many people can run first. Rule 1 says that T follows Q, so this question really means we have QT and S in.

That leaves only R and U. If R is in, then U is out. So, rule 2 applies (“If U is out, R goes 2nd”) and we get this scenario:

R is second, so only slots 3-4 have space for QT. S is left to go first.

So, we have proven that S can go first. Who else? 

Well, if U is in instead of R, then we could place the runners in this order:

(There is another possible order. We could so SUQT or even SQTU. But those add nothing, since we already proved S can go first)

So, only S and Q can go first. B is CORRECT.

Why can’t R, T and U go first?

• R can’t go first because rule 3 forces it second if U is out. (This question allows only one of R/U to be in, since QT and S are already in)
• T can’t go first because rule 1 places Q directly in front of T. (And this question places Q in).
• If U were first, S would have to go third, and that doesn’t leave two spaces open for QT. (S can’t go 2nd or 4th)

Time on second attempt: 9:40

See “repeating games” at bottom of section. One note I’ll make is that I did this section on scrap paper. I had no printer at the time I did this section.

Boy, did it make a difference! I felt much slower and hesitant. I think there’s massive value to diagrams immediately beside the questions. I also went slower because normally I cross off eliminated answers on my page. But since I was working from a screen, I could only draw letters on my scrap paper + cross them off on paper. When I looked at the screen, nothing was crossed off.

I strongly recommend printing or photocopying copies of games so you can mark up the pages themselves. It’s much more effective, and matches test day conditions. I suspect my actual time on real paper would have been much quicker.

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I find this to be a hard game, even though I’ve done it before. There are a lot of moving parts, and not really any upfront deductions. (At least none that I could find.)

I like to draw the simplest rule first. So we can draw rule 5, which says that L isn’t second:

This is a very important rule, because it is easy to forget. Make sure to always draw it under your diagram.

The first rule is a bit unusual. It says at least two nurses come in between H and M. I drew this with a plus:

• This is reversible, and there could be as many as five spaces between them. So we can’t combine this diagram with other ordering rules.

But, we can combine rules 2 and 4, because they both mention K:

Finally, rule 3 says M is before J:

That’s all I got. I couldn’t find any deductions. This is fairly common on newer LSATs: the games become entirely rule based.

However, though I didn’t make deductions, I did note that the L – F – GK group is extremely bulky. It takes up four spaces. Often, that means another variable will split it up. Remembering this quantity constraint will help you make deductions on questions.

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Repeating Games

I’ve written elsewhere about the benefits of repeating games, to solidify your intuition for deductions. Note that the purpose of repeating games is to prove the answers right, so it doesn’t matter if you remember the right answer.

I repeated this game about three days after I first saw it, by which time I had forgotten the answers. I’ve written how long it took me on the second attempt. That time, or a couple minutes above it, is roughly the standard you should be aspiring to – a lot of people take 8-9 minutes on a repeat attempt, get everything right, and pat themselves on the back. But that’s too slow. The faster you go when repeating, the faster you’ll learn to go the first time you see a game.

(I say “a couple minutes above” my time because, after years of teaching the LSAT, I’m really, really fast. You should be almost as fast as me, but you don’t exactly need to match my pace to score -0.)

Time on second attempt: 9:40

The setup section explains how to build this diagram.

Main Diagram

For acceptable order questions, go through the rules and use them to eliminate answers one by one.

Unusually, I started with the final rule. This was because it was easy to scan the answers to see if L was second. This eliminated two answers and helped finish the question faster.

Rule 5 eliminates B and E. L can’t go second. (Rule one also eliminates E, but starting with rule 5 is the most efficient method.)

Rule 2 eliminates nothing.

Rule 3 eliminates C. M is supposed to be earlier than J.

Rule 4 eliminates A. L is supposed to be before F.

D is CORRECT. It violates no rules.

I initially skipped this question. I figured later questions would produce hypothetical scenarios that eliminate answers.

I was right. Question 20 eliminates B by saying J can go third.

This diagram from question 21 shows that J can go last, which eliminates E:

This diagram from question 22 shows that J can go second, which eliminates A:

(Just imagine M, J, L and F floating down onto the diagram in that order. It’s a legal combination.)

That leaves only C and D left to compare. That makes this a much easier question. Let’s try drawing J 5th and 6th.

First, draw J fifth, and M somewhere before J (rule 3):

Then, consider the biggest rule. Our combined diagram for rules 2 and 4 shows the order must be
L – F – GK. That’s hard to fit in; it needs four spaces. There are only four spaces before J, and M is already filling on one of them. So, we must put L and F before J, and GK after.

H would also have to go before J. But, this won’t work. H and M have to be two spaces apart (rule 1) and L can’t go second (rule 5). There’s no way to obey both of those rules. So C is CORRECT.

(Two spaces apart is 1st and 4th, which would force L – F into 2nd and 3rd. And, as I said, L can’t go 2nd.)

Let’s prove D can work, to be sure we haven’t made a mistake (When doing games under timed conditions, mistakes are easy.) We end up with this:

M goes before J thanks to rule 3. L – F – GK go before J because there’s no space to put GK after J. That leaves H to go after J, obeying rule one.

We just have to place the variables before J. This order works:

This question places J 3rd. We also know from rule 3 that M goes before J, so you should draw that as well:

M before J forces H to go after J – they must be at least two spaces apart. (rule 1)

What next? The L – F – GK block requires four spaces. That means they can’t all fit after J. So L, the start of the block, must go before J. This means L goes first, since it can’t go second (rule 5):

This forces H to go 5th or later, to obey rule 1. That means F must go fourth (so it can be before GK).

So our only two possibilities for 5-6-7 are:

• HGK
• GKH

This solves the question. D is CORRECT.

This question places K before M. When a question gives you a new rule, you should look at the existing rules and see which ones are affected.

The new rule was an ordering rule. In the setup, we had two ordering rules which involved K and M:

To solve this question, just combine those two diagrams to place K before M:

This places every variable except H in order. Rule 1 mentions H: it has to be at least two spaces away from M. In this case, that means H must go before GK, since that gives us the necessary two spaces:

Based on that diagram, either H or F could be third. So B is CORRECT.

This question places G fifth. We know that G is part of this ordering rule: L – F – GK

So, we must put K sixth (rule 2):

Who can go last? Not L or F: they’re before GK. Not M: they’re before J. So only H and J can go last. Let’s try drawing both. We’ll start with H last:

Who is left to place? M – J and L – F:

This seems to work. We can place these in any order as long as we obey the two ordering rules, and don’t place L second.

What about J last? Let’s try that:

Who is left? H and M, and L – F. H and M must be at least two spaces apart (rule 1), so we have to place them in 1 and 4, in either order:

Only L – F are left. But this doesn’t work, because it would force L second! So J can’t be last.

Therefore, H must be last. B is CORRECT. 

I like using past scenarios to solve questions. We just made this working scenario for question 22:

If you imagine the variables floating down in the order MJLF, you can see that L can go third. There’s no rule against it! A is CORRECT.

You might be wondering how to solve this question without 22. Well, you can eliminate some answers. For example, the L – F – GK group is quite restrictive. L has three things after it, so L could go fourth at latest. That eliminates C, D and E.

But L actually can’t go fourth, either. We’d end up with this diagram:

M and H are too close together, which violates rule 1.