Critical Thinking Exercises (With Worked Solutions)
A hands-on library of critical thinking exercises with fully worked solutions — for adults, students and teams. Work through each one, then check your reasoning against the explanation.
Reading about critical thinking rarely makes you better at it — practising does. Below are ten exercises, one or two per core reasoning skill, each with a fully worked solution. Work out your own answer first, then open the solution and compare your reasoning to the explanation. When you are ready to measure yourself, take the free critical thinking test.
1. The marketing claim
A team lead says: "We should move our whole ad budget to TikTok — that's where our customers are." What is she assuming?
Show the worked solution
She is assuming (a) that a meaningful share of the target customers actually use TikTok, and (b) that ad spend there will reach them effectively. Spotting the unstated assumption is the first move in evaluating any claim: ask "what would have to be true for this to make sense?"
2. The sales figures
A shop sold out of umbrellas on 9 of the 10 rainiest days last month, and on none of the dry days. What can you reasonably infer — and what can you not?
Show the worked solution
You can reasonably infer that umbrella demand rose with rain. You cannot infer the shop made a profit, that it stocked enough umbrellas, or that rain caused the sales (correlation is not proof of cause, though here it is strongly suggestive). Good inference separates "very likely" from "certain" and refuses to over-read the data.
3. The valid conclusion
All members of the safety team are trained in first aid. Priya is not trained in first aid. Does it follow that Priya is not on the safety team?
Show the worked solution
Yes — it follows necessarily. If every safety-team member is first-aid trained, then anyone lacking that training cannot be a member (this is valid "modus tollens"). Contrast this with the invalid version: "Priya is first-aid trained, therefore she is on the safety team" — that does not follow, because non-members can be trained too.
4. Strong vs weak argument
Question: should the office switch to a four-day week? Argument: "Yes — a six-month trial at a similar firm cut sick days by 30% and kept output flat." Is this a strong or weak argument?
Show the worked solution
Strong. It is directly relevant to the proposal and backed by comparable evidence (a trial, with measurable outcomes). A weak version would be "Yes — Fridays off would be nice," which is merely a preference with no bearing on whether the switch is a good business decision.
5. Reading the passage
A report states: "After the new onboarding programme, first-year staff turnover fell from 25% to 12%, while hiring volume was unchanged." Conclusion offered: "The onboarding programme was the sole reason turnover fell." Warranted?
Show the worked solution
Not warranted. The passage supports "turnover fell after the programme" and even "the programme plausibly contributed." But "sole reason" rules out every other factor (pay changes, the job market, who was hired) — which the passage cannot establish. Interpretation means accepting only what the evidence actually supports.
6. The hidden premise
"We must keep prices low or we'll lose customers to competitors." What does this argument take for granted?
Show the worked solution
It assumes price is the main thing keeping customers — i.e. that customers are price-sensitive and would switch for a lower price elsewhere. If customers actually stay for service, quality, or convenience, the argument collapses. Naming the assumption lets you test it instead of accepting it.
7. Survey caution
An online poll on a gaming website finds 80% of respondents oppose a new tax. A columnist writes: "The public opposes the tax." What is wrong with the inference?
Show the worked solution
The sample is not the public. People who answer a poll on a gaming site are self-selected and unrepresentative, so the 80% says little about the general population. The skill here is spotting biased sampling before generalising from a number.
8. The conditional trap
Rule: "If a file is confidential, it is stored in the locked cabinet." A file is in the locked cabinet. Does it follow that the file is confidential?
Show the worked solution
No. The rule only tells you what happens to confidential files; it does not say the cabinet holds nothing else. Concluding "in the cabinet, therefore confidential" is the classic error of affirming the consequent. The cabinet could also hold spare keys or stationery.
9. Spotting the fallacy
Question: should the city fund more bike lanes? Argument: "No — the councillor who proposed it once got a parking ticket, so he can't be trusted on traffic." Strong or weak?
Show the worked solution
Weak — it is an "ad hominem": it attacks the person instead of the proposal. Whether bike lanes are worthwhile depends on safety, cost, and usage data, not on the proposer's parking history. Strong arguments engage the issue; weak ones attack the messenger.
10. Put it together
"Our app's rating dropped from 4.6 to 4.1 after the redesign, so the redesign was a failure and we should roll it back." Find the assumption, judge the inference, and evaluate the argument.
Show the worked solution
Assumption: that the rating drop was caused by the redesign and reflects overall success. Inference: a drop after the redesign is suggestive but not conclusive — ratings can fall because of a bug, a price change, or a vocal minority. Evaluation: "failure, roll it back" is too strong on this evidence; a careful thinker would first check what reviewers actually complain about and whether usage or revenue also fell before deciding. This is exactly the layered reasoning the full test measures.
How to get the most from these exercises
Treat each one as a tiny experiment. Commit to an answer in writing before you reveal the solution — the act of committing is what builds the skill, because it forces you to notice the gap between what you assumed and what the evidence actually supports. Ten minutes a day beats one long session a week.
What to do after the exercises
Once these feel comfortable, take the critical thinking test to see your score broken down by skill, then read how to improve your critical thinking for the daily habits that turn occasional practice into a durable thinking style.
Frequently asked questions
What are good critical thinking exercises?
The most effective exercises force you to separate facts from assumptions, test whether a conclusion really follows, and weigh evidence on both sides. The exercises on this page — inference, recognising assumptions, deduction and argument evaluation — mirror the five skills measured by standardised reasoning tests.
How can I practise critical thinking on my own?
Pick one short scenario, write down your answer before reading the solution, then compare your reasoning to the worked explanation. Doing this daily for ten minutes builds the habit faster than passively reading about critical thinking.
Are these exercises suitable for adults and students?
Yes. Each exercise works for adults, college and high-school students. The scenarios are everyday and self-contained, so no prior subject knowledge is needed — only careful reasoning.