A collection of challenging quizzes for adults [Difficult]
Feeling the urge to tackle a brain-busting puzzle that seems impossible—“No one could solve this!”—might be a uniquely adult kind of curiosity.
But why do puzzles and riddles that hinge on sudden insight make your heart race? It’s because your brain is seeking that moment of activation.
This time, we’ve handpicked challenging problems for adults that test flexible thinking and ideas unconstrained by common sense.
Don’t overthink them—try looking from a slightly different angle.
The “aha!” moment is surely waiting for you.
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Difficult Logic & Exam-Type Quizzes (For Job Applicants, Examinees, and Geniuses) (1–10)
[Logic Quiz] Extremely Difficult! A Room with 23 Men and Chairs
![[Logic Quiz] Extremely Difficult! A Room with 23 Men and Chairs](https://i.ytimg.com/vi/hx5q1y5UxXA/sddefault.jpg)
This is a puzzle about devising a strategy that allows all 23 men to escape, based on their actions when they are led into a room with a chair.
In the chair room, each person can choose either to rotate the chair by 90 degrees or to break the chair; if someone chooses to break the chair, everyone who has entered up to that point is allowed to escape.
The key is that they can confer beforehand, so the challenge is how to use the chair’s orientation to communicate that everyone has entered.
Let’s combine various patterns and possibilities—such as counting via orientation and cases where escape is not yet possible—to derive an appropriate method.
Microsoft’s entrance exam for new employees
Let’s take on questions from the entrance exam of Microsoft, a globally renowned company, and see whether you have what it takes to join.
These problems don’t just test simple academic ability; they also challenge flexible thinking and the capacity to organize things logically.
You’ll work through specified conditions, perform calculations that account for the given situations, and tackle the problems by combining a broad range of knowledge.
People with strong organizational skills can get close to the answer on their own, but it’s also fun to enjoy the feeling of gradually unraveling the mystery by receiving well-timed hints.
Apple’s entrance exam
This is a problem that was used in Apple’s employment exam—a famous global company known for products like the Mac and iPhone.
When you think of corporate hiring tests, you might imagine that they mainly assess academic ability, but these problems test not only that, they also gauge creativity and flexible thinking.
While meeting the specified conditions and scenarios, you work your way toward an answer; what matters most is organizing things step by step.
Because these are challenging problems that require combining knowledge with inventive thinking, it’s important to provide appropriate hints if someone finds them too difficult to solve.
Entrance exam questions for highly competitive junior high schools
This is a problem about finding angles in a figure.
For those who aren’t good at math, it might be quite baffling.
It should be solvable with elementary school knowledge, but it’s still quite challenging.
As expected, it’s an entrance exam question from a highly competitive junior high school.
Please try it with the mindset of an elementary school student!
Mathematics Probability Problem
The prisoner’s paradox, often explained in the context of solving the Monty Hall problem posed in probability theory.
It’s a quiz that asks whether your chances of survival increase if, among three prisoners with only one destined to be spared, you learn in advance who will not be spared.
Although it’s a problem themed around mathematical probability, there’s no need to think in a complicated way.
By following your intuition, you can arrive at the correct answer.
It’s an extremely challenging puzzle packed with the allure of paradoxes—where seemingly sound logic leads to an unsettling conclusion.
