[Genius if you can solve it?] Insight and intuition: a challenging IQ quiz
That instant when an idea pops into your head feels so good, doesn’t it? Why not try some IQ quizzes that train your intuition and creativity and enjoy that refreshing rush? Discovering the “Aha!” moment when you see the answer is part of the fun, too.
From wordplay and number tricks to puzzles that use the characteristics of kanji, a small shift in perspective can reveal the solution.
Take a short break in your day and enjoy IQ quizzes as a way to refresh your brain.
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- [Challenging and Fun!] Quizzes & Riddles for Adults
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- [Interesting] A collection of brain teaser quiz questions. Let's train your brain!
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- [Personality Test] Are You a Smart Person? A Thorough Diagnosis of Your Abilities and Talents!
Simple but Profound Logical Thinking and Trick-Style IQ Quizzes (11–20)
When a train traveling east at 40 km/h is hit by a south wind blowing at 5 km/h, in which direction does the train’s smoke drift?
See the answer
Since it's a train, there is no smoke.
I bet some of you ended up picturing an SL (steam locomotive) running in your head while reading the problem statement. The specific speeds and directions served as a hook, making it a tricky question.
Which is heavier, 10 tons of iron or 10 tons of paper?
See the answer
Both are the same.
When you hear the words iron and paper, some people might feel that iron seems heavier at first glance. The key is to realize that the weight of 10 tons doesn’t change, so they’re the same weight. Don’t overthink the question—just compare the weight simply.
When you toss a 10-yen coin and it falls to the ground, what percentage is the probability that the side with the number faces up?
See the answer
100%
Some of you might have wondered about the probability of the side labeled “10” coming up. However, a 10-yen coin has both the Arabic numeral “10” and the kanji character “十” engraved on its two faces, so whichever side lands face up, a “number” is on top.
There are two incense sticks that each burn out in one hour. How can you use them to measure 45 minutes?
See the answer
Light three points simultaneously: one stick at one end, the other stick at both ends. When the first stick burns out, light the remaining end of the other stick.
An incense stick lit at both ends should burn out in 30 minutes. If you light one end first, by the time it has 30 minutes of burn time remaining, lighting the other end will make it burn twice as fast, so 30 ÷ 2 = 15 minutes, and everything will burn out in a total of 45 minutes.
The hot water I boiled in a kettle was gone after five hours. Why on earth did that happen?
See the answer
Because it had turned into water
Because five hours had passed since the water was boiled, it had cooled down and turned into water. The phrase “had disappeared” makes you think the hot water vanished somewhere, but the trick is noticing that its state had changed.



