woman solving a brain teaser at her computer

This Tricky Brain Teaser Is Blowing People’s Minds! But Can You Do It?

Here’s a new brain teaser to test your problem-solving skills. Warning: It does contain violence against books, so if you are sensitive to that, you have been warned. If you can’t guess the right answer immediately, don’t give up! A new study discovered a way of thinking that’s most effective in problem-solving. The answer to the riddle is at the end of the post so you could first learn the scientifically proven method to solve puzzles.


Here is the Brain Teaser:

Brain teaser: My son was playing with a book and tore out pages 7, 8, 100, 101, 22, and 223. How many pages were torn out?
Photo Credits: Smalljoys.tv

Do you know the answer? If you don’t, here’s a way to find out. If you did guess it, the study may be helpful to know for other riddles.


The Study of Solving Riddles

Researchers have studied the art of solving a brain teaser. Using 200 volunteers, a computer model, and MRI images, a study from the University of Washington discovered more about the process of reasoning and how problem-solving could go wrong.


There are two fundamental ways your brain can steer you through life — toward things that are good, or away from things that aren’t working out,” said Chantel Prat, associate professor of psychology and co-author of the new study. “Because these processes are happening beneath the hood, you’re not necessarily aware of how much driving one or the other is doing.” [1]

So the researchers measured how much “steering” involves the brain when it comes to rewarding things versus less rewarding things. Essentially, Prat and her colleagues wanted to understand what makes someone good at solving riddles, essentially, the brain steering toward a right answer or steering away from the wrong answers. To do this, they used a test of puzzles involving patterns and predicting the next digit in the sequence.


They evaluated the computer model’s progress based on the four steps to solve a brain teaser: identifying a key feature in the sequence, seeing where the feature is in the sequence, inventing a rule for changing the feature, and seeing if the rule works for the rest of the pattern. The researchers found the model succeeded more when it steered away from unhelpful features and patterns. In short, knowing when your “train of thought is on the wrong track” is key to solving the problem.


Dismiss the Bad Options First

Then they tested if this was true in people. So they divided the volunteers into three groups. The first solve riddles with a pen and paper. Their results showed that the ability to “avoid” bad options was important to solve problems. Additionally, the ability to “choose” the best option wasn’t relevant to effectively solving the puzzle.


When the researchers connected the second group with MRI scans as they solved the computerized versions of the brain teaser, the results confirmed the first group. The best problem-solvers were the ones best at avoiding the bad options. The third group confirmed this with computerized puzzles and having the participants’ brain activities be recorded via fMRI. Moreover, when the part of the brain that makes decisions focuses on avoiding bad choices, the participants were more successful at solving puzzles. Meaning, you have to know what’s not working in order to find what does work.


Our brains have parallel learning systems for avoiding the least good thing and getting the best thing,” said Prat. “A lot of research has focused on how we learn to find good things, but this pandemic is an excellent example of why we have both systems. Sometimes, when there are no good options, you have to pick the least bad one! What we found here was that this is even more critical to complex problem-solving than recognizing what’s working.”

So don’t be discouraged if you don’t think of the correct answer to the brain teaser right away. It may be more helpful to determine what is the wrong answer first and building from that. So without further ado…


The Correct Answer to the Brain Teaser

The answer is…

brain teaser answer

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  1. “Can’t solve a riddle? The answer might lie in knowing what doesn’t work.” Science Daily. The University of Washington. March 4, 2021
Sarah Biren
Freelance Writer
Sarah is a baker, cook, author, and blogger living in Toronto. She believes that food is the best method of healing and a classic way of bringing people together. In her spare time, Sarah does yoga, reads cookbooks, writes stories, and finds ways to make any type of food in her blender.