LSAT Logical Reasoning Practice Questions
Free, original LSAT-style logical reasoning practice questions — each with a full explanation of why every answer choice is right or wrong, plus a breakdown of the main question types. Practice the reasoning the LSAT actually rewards.
Logical Reasoning is about half of your scored LSAT questions, so it is the highest-leverage section to practise. Below are five original, LSAT-style questions — each with the question type, the correct answer, and a full explanation of why every choice is right or wrong. Work the question before you reveal the answer: identify the type, find the conclusion and support, and predict the answer first.
These are original practice items written to mirror the LSAT format and difficulty. They are not real LSAC questions, which are copyrighted — use these alongside official prep.
Question 1
A city replaced its streetlights with brighter LED lights, and over the following year nighttime traffic accidents fell by 15%. Clearly, the brighter lighting made the roads safer.
Which one of the following, if true, most weakens the argument?
- A) The LED lights used less electricity than the old lights.
- B) During the same year, the city also lowered the nighttime speed limit on its busiest roads.
- C) Some residents complained that the new lights were too bright.
- D) Daytime accident rates were unchanged over the year.
- E) Neighbouring cities did not replace their streetlights.
Answer & explanation
Correct answer: B. The argument assumes the lighting caused the drop. (B) supplies an alternative cause — a lower speed limit introduced at the same time — which could explain the fall instead. (A) and (C) are irrelevant to safety outcomes; (D) and (E) do nothing to rule out the lighting as the cause.
Question 2
The new employee wellness program must be working: since it launched, the number of sick days taken by staff has dropped sharply.
The argument depends on assuming which one of the following?
- A) The wellness program is popular with employees.
- B) The drop in sick days was not caused mainly by some other factor, such as a milder flu season.
- C) Every employee participates in the wellness program.
- D) Sick days are the best possible measure of employee health.
- E) The program was inexpensive to run.
Answer & explanation
Correct answer: B. For "the program is working" to follow from fewer sick days, the speaker must assume the drop was not really caused by something else. Negate (B) — if a milder flu season caused it — and the argument collapses, so (B) is necessary. (C) is too strong; (A), (D) and (E) are not required for the conclusion.
Question 3
People who drink green tea tend to live longer than those who do not. Therefore, drinking green tea causes a longer life.
The argument is most vulnerable to criticism on the grounds that it…
- A) fails to consider that another factor, such as generally healthier habits among tea drinkers, could explain both the tea-drinking and the longer life.
- B) does not specify how much green tea must be consumed.
- C) assumes that living longer is desirable.
- D) relies on the testimony of experts.
- E) draws a conclusion about individuals from facts about groups.
Answer & explanation
Correct answer: A. This is the classic mistake of treating a correlation as proof of causation. (A) names the confounding factor that could produce both at once. (B) and (C) raise side issues; (D) misdescribes the argument; (E) does not match the reasoning, which is about cause, not group-to-individual inference.
Question 4
All members of the debate club are also in the honour society. No one in the honour society failed the final exam.
If the statements above are true, which one of the following must also be true?
- A) Everyone in the honour society is in the debate club.
- B) No member of the debate club failed the final exam.
- C) Some honour society members are not in the debate club.
- D) Everyone who passed the exam is in the debate club.
- E) Some debate club members failed the exam.
Answer & explanation
Correct answer: B. Debate club members are all in the honour society, and no honour-society member failed — so no debate club member failed (B). (A) reverses the relationship; (C), (D) and (E) are not guaranteed by the premises.
Question 5
The museum's new late-night opening hours will increase its total visitors. After all, a survey found that many people say they cannot visit during the day because of work.
Which one of the following, if true, most strengthens the argument?
- A) The museum's daytime visitor numbers have been stable for years.
- B) People who say they cannot visit during the day would in fact come in the evening if the museum were open then.
- C) The museum will need to hire additional evening staff.
- D) Other museums in the city are not open late.
- E) The survey was conducted online.
Answer & explanation
Correct answer: B. The argument assumes the day-blocked people will actually turn up in the evening. (B) confirms exactly that link, strengthening the conclusion. (A) is neutral, (C) is a cost not a benefit, (D) is irrelevant to this museum's demand, and (E) bears on the survey's quality, not the conclusion.
The main LSAT logical reasoning question types
Spotting the question type first tells you what move to make. The most common:
| Question type | What it asks you to do |
|---|---|
| Assumption | Find the unstated premise the argument needs (necessary) or one that would complete it (sufficient). |
| Strengthen / Weaken | Add a new fact that makes the conclusion more or less likely — usually by confirming or breaking the key assumption. |
| Flaw | Name the reasoning error: correlation-causation, unrepresentative sample, circular reasoning, etc. |
| Inference (must be true) | Pick the choice that has to be true given the statements — no outside assumptions. |
| Main point | Identify the conclusion the rest of the argument supports. |
| Parallel reasoning | Match the logical structure of the argument, not its topic. |
How to get better at LSAT logical reasoning
- Identify the question type before reading the choices — it tells you what to look for.
- Find the conclusion and the support, and name the gap between them.
- Predict the answer in your own words, then match it to a choice.
- Review every wrong choice and say why it is wrong — the habit every explanation above models.
Want a warm-up first? The general logical reasoning test and logical reasoning guide build the underlying skills; the critical thinking test sharpens the assumptions-and-evidence thinking the LSAT rewards.
A recommended LSAT prep course will be linked here soon.
Frequently asked questions
How many logical reasoning questions are on the LSAT?
The LSAT includes two scored Logical Reasoning sections of about 24–26 questions each, so Logical Reasoning makes up roughly half of your scored questions — which is why it is the highest-leverage section to practise.
What are the main LSAT logical reasoning question types?
The most common are: assumption, strengthen/weaken, flaw, inference (must be true), main point, principle, parallel reasoning and method of reasoning. Each rewards a slightly different move, so learning to spot the question type first is half the battle.
Are these real LSAT questions?
No. These are original, LSAT-style practice questions written to mirror the format and difficulty. Real LSAT questions are copyrighted by LSAC; practising on faithful originals plus official prep is the safe, effective combination.
How do I get better at LSAT logical reasoning?
Identify the question type, find the conclusion and the support, and predict the answer before reading the choices. Then review why each wrong choice is wrong — that habit, which every explanation here models, is what raises your score.