Logical Reasoning Sample Questions With Answers

Now that we’ve reviewed the LSAT's common questions, here are some sample LR practice questions and their answers.

Question One

Laird: Pure research provides us with new technologies that contribute to saving lives. Even more worthwhile than this, however, is its role in expanding our knowledge and providing new, unexplored ideas.

Kim: Your priorities are mistaken. Saving lives is what counts most of all. Without pure research, medicine would not be as advanced as it is.

Laird and Kim disagree on whether pure research

1. derives its significance in part from its providing new technologies
2. expands the boundaries of our knowledge of medicine
3. should have the saving of human lives as an important goal
4. has its most valuable achievements in medical applications
5. has any value apart from its role in providing new technologies to save lives

Answer and Explanation

The correct answer to this question is D. Laird argues pure research’s most valuable purpose is to expand knowledge. In contrast, Kim argues that its most useful purpose is in medical applications, which is to save lives. 

Option D is correct because Kim would agree with it, and Laird would disagree.

Question Two

During the construction of the Quebec Bridge in 1907, the bridge’s designer, Theodore Cooper, received word that the suspended span being built out from the bridge’s cantilever was deflecting downward by a fraction of an inch (2.54 centimeters).

Before he could telegraph to freeze the project, the whole cantilever arm broke off and plunged, along with seven dozen workers, into the St. Lawrence River. It was the worst bridge construction disaster in history.

As a direct result of the inquiry that followed, the engineering “rules of thumb” by which thousands of bridges had been built around the world went down with the Quebec Bridge. Twentieth-century bridge engineers would thereafter depend on far more rigorous applications of mathematical analysis.

Which one of the following statements can be properly inferred from the passage?

1. Bridges built before about 1907 were built without thorough mathematical analysis and, therefore, were unsafe for the public to use.
2. Cooper’s absence from the Quebec Bridge construction site resulted in the breaking off of the cantilever.
3. Nineteenth-century bridge engineers relied on their rules of thumb because analytical methods were inadequate to solve their design problems.
4. Only a more rigorous application of mathematical analysis to the design of the Quebec Bridge could have prevented its collapse.
5. Prior to 1907, the mathematical analysis incorporated in engineering rules of thumb was insufficient to completely assure the safety of bridges under construction.

Answer and Explanation

E is the correct answer because it is the only choice that makes a logical inference based on the information presented. The passage indicates that the Quebec Bridge disaster occurred in 1907 and caused the engineering “rule of thumbs” to stop being used. 

As such, it can be inferred that this 1907 disaster bridge, and the ones before it, used the rule of thumbs and that these rules were insufficient to completely assure the safety of the bridges since the Quebec bridge collapsed. 

Question Three

The supernova event of 1987 is interesting in that there is still no evidence of the neutron star that current theory says should have remained after a supernova of that size. 

This is in spite of the fact that many of the most sensitive instruments ever developed have searched for the tell-tale pulse of radiation that neutron stars emit. Thus, current theory is wrong in claiming that supernovas of a certain size always produce neutron stars.

Which one of the following, if true, most strengthens the argument?

1. Most supernova remnants that astronomers have detected have a neutron star nearby.
2. Sensitive astronomical instruments have detected neutron stars much farther away than the location of the 1987 supernova.
3. The supernova of 1987 was the first that scientists were able to observe in progress.
4. Several important features of the 1987 supernova are correctly predicted by the current theory.
5. Some neutron stars are known to have come into existence by a cause other than a supernova explosion.

Answer and Explanation

The correct answer to this question is B. The main argument is that the current theory that supernovas of a certain size always produce neutron stars is wrong. The proof used to support this claim is that the 1987 supernova event did not produce a neutron star even after sensitive instruments searched for it. 

Answer B bridges a gap in this evidence by proving that these sensitive instruments have detected neutron stars much further away, demonstrating it wasn’t simply an error in the technology or range limitations that failed to detect a neutron star. 

Question Four

Political scientist: As a political system, democracy does not promote political freedom. There are historical examples of democracies that ultimately resulted in some of the most oppressive societies. Likewise, there have been enlightened despotisms and oligarchies that have provided a remarkable level of political freedom to their subjects.

The reasoning in the political scientist’s argument is flawed because it

1. confuses the conditions necessary for political freedom with the conditions sufficient to bring it about    
2. fails to consider that a substantial increase in the level of political freedom might cause a society to become more democratic
3. appeals to historical examples that are irrelevant to the causal claim being made
4. overlooks the possibility that democracy promotes political freedom without being necessary or sufficient by itself to produce it
5. bases its historical case on a personal point of view

Answer and Explanation

D is the correct response. The argument fails to recognize that even if democracy is insufficient for political freedom, it can, in most instances, promote it by contributing to it. 

Likewise, even if democracy is not necessary for political freedom, it can still be true that democracy promotes political freedom wherever it is found.

Question Five

About two million years ago, lava dammed up a river in western Asia and caused a small lake to form. The lake existed for about half a million years. Bones of an early human ancestor were recently found in the ancient lake-bottom sediments that lie on top of the layer of lava. Therefore, ancestors of modern humans lived in western Asia between two million and one-and-a-half million years ago.

Which one of the following is an assumption required by the argument?

1. There were no other lakes in the immediate area before the lava dammed up the river.
2. The lake contained fish that the human ancestors could have used for food.
3. The lava that lay under the lake-bottom sediments did not contain any human fossil remains.
4. The lake was deep enough that a person could drown in it.
5. The bones were already in the sediments by the time the lake dried up.

Answer and Explanation

E is the assumption required by the argument, and it is the only one directly relevant to the argument. If the bones weren't initially in the sediment as the lake dried up, it implies they must have entered the sediment later, specifically less than one-and-a-half million years ago. 

However, this would mean that the bones wouldn't serve as evidence for the presence of human ancestors in western Asia between two million and one-and-a-half million years ago. In other words, if E is false, the argument's conclusion wouldn't be valid!

Question 6

Journalist: To reconcile the need for profits sufficient to support new drug research with the moral imperative to provide medicines to those who most need them but cannot afford them, some pharmaceutical companies feel justified in selling a drug in rich nations at one price and in poor nations at a much lower price. But this practice is unjustified. A nation with a low average income may still have a substantial middle class better able to pay for new drugs than are many of the poorer citizens of an overall wealthier nation.

Which one of the following principles, if valid, most helps to justify the journalist’s reasoning?

1. People who are ill deserve more consideration than do healthy people, regardless of their relative socioeconomic positions.
2. Wealthy institutions have an obligation to expend at least some of their resources to assist those incapable of assisting themselves.
3. Whether one deserves special consideration depends on one’s needs rather than on characteristics of the society to which one belongs.
4. The people in wealthy nations should not have better access to health care than do the people in poorer nations.
5. Unequal access to health care is more unfair than an unequal distribution of wealth.

Answer and Explanation

The correct answer here is C. Pharmaceutical companies consider societal characteristics, not personal needs. In doing this, they overlook the poorer citizens of wealthier nations, provide unneeded aid to middle-class citizens of poorer nations, and fail to generate income for drug research. 

Question 7

Several critics have claimed that any contemporary poet who writes formal poetry—poetry that is rhymed and metered—is performing a politically conservative act. This is plainly false. Consider Molly Peacock and Marilyn Hacker, two contemporary poets whose poetry is almost exclusively formal and yet who are themselves politically progressive feminists.

The conclusion drawn above follows logically if which one of the following is assumed?

1. No one who is a feminist is also politically conservative.
2. No poet who writes unrhymed or unmetered poetry is politically conservative.
3. No one who is politically progressive is capable of performing a politically conservative act.
4. Anyone who sometimes writes poetry that is not politically conservative never writes poetry that is politically conservative.
5. The content of a poet’s work, not the work’s form, is the most decisive factor in determining what political consequences, if any, the work will have.

Answer and Explanation

The only answer that works here is C. The core of the argument is about political conservativeness versus political progressiveness. If Peacock and Hacker are both politically progressive and yet write formal poetry, then writing formal poetry cannot be a politically conservative act. 

Question 8

Executive: We recently ran a set of advertisements in the print version of a travel magazine and on that magazine’s website. We were unable to get any direct information about consumer response to the print ads. However, we found that consumer response to the ads on the website was much more limited than is typical for website ads. We concluded that consumer response to the print ads was probably below par as well.

The executive’s reasoning does which one of the following?

1. bases a prediction of the intensity of a phenomenon on information about the intensity of that phenomenon’s cause
2. uses information about the typical frequency of events of a general kind to draw a conclusion about the probability of a particular event of that kind
3. infers a statistical generalization from claims about a large number of specific instances
4. uses a case in which direct evidence is available to draw a conclusion about an analogous case in which direct evidence is unavailable
5. bases a prediction about future events on facts about recent comparable events

Answer and Explanation 

The answer D correctly identifies the executive’s reasoning. The executive made an analogy using evidence about the website ads to infer a conclusion about the print ads, although that specific evidence was unavailable to them. 

Question 9 

In jurisdictions where use of headlights is optional when visibility is good, drivers who use headlights at all times are less likely to be involved in a collision than are drivers who use headlights only when visibility is poor. Yet Highway Safety Department records show that making use of headlights mandatory at all times does nothing to reduce the overall number of collisions.

Which one of the following, if true, most helps to resolve the apparent discrepancy in the information above?

1. In jurisdictions where use of headlights is optional when visibility is good, one driver in four uses headlights for daytime driving in good weather.
2. A law making use of headlights mandatory at all times is not especially difficult to enforce.
3. Only very careful drivers use headlights when their use is not legally required.
4. There are some jurisdictions in which it is illegal to use headlights when visibility is good.
5. The jurisdictions where use of headlights is mandatory at all times are those where daytime visibility is frequently poor.

Answer and Explanation

Response C is correct, as it fills the gap between the headlight laws and the number of collisions. Careful drivers are likelier to use headlights even when they’re not mandatory, showing why they are less likely to be involved in a crash than drivers who only use headlights when necessary. 

Question 10

The Venetian Renaissance painter Vittore Carpaccio used sumptuous reds in most of his paintings. Since the recently discovered Venetian Renaissance painting Erato Declaiming contains notable sumptuous reds, it is probably by Carpaccio.

Which one of the following contains a pattern of flawed reasoning most similar to that in the argument above?

1. Most Renaissance painters worked in a single medium, either tempera or oil. Since the Renaissance painting Calypso's Bower is in oil, its painter probably always used oil.
2. In Italian Renaissance painting, the single most common subject was the Virgin and Child, so the single most common subject in Western art probably is also the Virgin and Child.
3. Works of art in the Renaissance were mostly commissioned by patrons, so the Renaissance work The Dances of Terpsichore was probably commissioned by a patron.
4. The anonymous painting St. Sebastian is probably an early Florentine painting since it is in tempera, and most early Florentine paintings were in tempera.
5. Since late-Renaissance paintings were mostly in oil, the Venetian late-Renaissance painter Arnoldi, whose works are now lost, probably painted in oil.

Answer and Explanation 

The response with the most similar flaw to the question is D. Just because most Florentine paintings were in tempura does not mean that one particular tempura painting must be Florentine. 

This argument uses the same flaw as the question. Just because most Carpaccio paintings used sumptuous reds, it does not mean that one particular painting with sumptuous reds must be by Carpaccio.

Tips in Preparing and Answering the LSAT Logical Reasoning Section

You’ll need to prepare well to ace Logical Reasoning. Here are our top tips for improving your logical reasoning skills on the LSAT and preparing for test day.

Tip #1: Familiarize Yourself With Question Types

The best way to prepare for the LR section is to familiarize yourself with the standard question types. Some questions, like Strengthen and Helping Hand, look similar but are not. Knowing each question type gives you a better idea of what to look for in the answer choices.

Tip #2: Take a Diagnostic Test

Before creating a comprehensive study schedule, you should begin with a diagnostic test to assess your baseline abilities. This schedule should involve as many LR practice questions as possible under timed conditions. These will help you develop good problem-solving strategies to answer the questions easier!

Tip #3: Take Your Time When Preparing

Taking practice tests under the same time limits that you’ll face on the exam is an excellent idea. But if you’re just starting to study, you should try to answer questions without any time limits. This way, you can avoid rushing and making simple errors. 

Taking your time will help you effectively practice identifying the parts of the argument. Then, when you’re ready, you can move on to timed tests when your skills are more solidified. 

Tip #4: Build a Test Prep Schedule 

A solid study schedule will ensure you have enough time to prepare well. You won’t have to cram the week before the test; instead, you’ll be able to sharpen up your skills, identify your weak areas, and focus on areas for improvement well in advance. 

Tip #5: Study With Peers

Sitting down to tackle some LSAT LR questions with classmates can make a big difference since your peers have skills and perspectives that you don’t, and vice versa. Studying with others can open your eyes to new ways of thinking. You might learn strategies from them that you wouldn’t have discovered alone!

Tip #6: Read the Question First

Read the question first instead of the passage to avoid having to re-read the passage to find what you’re looking for.

Tip #7: Don’t Make Unsupported Assumptions

Any inferences you make must be made directly from the passage. If the right answer goes against everything you know but logically follows the information in the passage, it is correct regardless of your own opinions or knowledge. 

Tip #8: Skip Questions

Don’t fixate on hard questions for too long. If you find yourself getting stuck on a question, move on to the next and come back to it if you have time. Answer as many questions as you can and then guess on any you don’t have time to finish. You should never leave a question blank because you still have a chance of guessing correctly.

Tip #9: Read Carefully

Misreading just one or two words can cost you several points on the LSAT. Ensure you are an active and engaged reader throughout your exam. For the LR section, in particular, keep track of the type of language being used. 

For instance, words like “never” and “always” are powerful words that will likely be repeated in the correct answer choice and weakened to “sometimes” or “most of the time” in incorrect decisions. 

Additionally, you always want to look out for words like EXCEPT, which will always be bolded.

Tip #10: Don’t Focus on the Vocab

The questions in the LR section often use complicated terms and topics because it easily psychs students out. Do your best to focus on the arguments, not the vocab. If there are words you don’t understand, just replace them with words you do! The exact words themselves aren’t necessary, just the argument itself and its structure.