The Ukrainian Grabarchuk family is known for making such puzzles and is quite famous around the world. It also has books, websites and apps.
The puzzles they prepare are as entertaining as they are instructive. We have compiled the most interesting ones among them, let’s see if they can be of interest to you as well.
Note: Solutions are at the end of the content.
1. Which ring system is different from the others?
2. One of these snakes, consisting of 11 cubes, is faulty. Which one?
3. Behind this seemingly meaningless puzzle lies a mystery: Which of the following signs should replace the question mark?
4. Which number should replace the question mark?
5. The numbers you put in the boxes should be able to give correct results in down and sideways operations.
Now let’s move on to the solutions:
1. A, B, and C have one loop free, but D are all looped.
2. If you look carefully, you can see the difference.
3. These signs are actually created with mirrored versions of italicized numbers.
4. Numbers indicate how many cells with a number in them are touched. So the blue cell should be 2 because it is touching two cells with numbers in it (i.e. 3 and 4).
5. A somewhat tedious question, but well worth the effort.
Who can do 5 out of 5?
Sources: Grabarchuk Puzzles, The Guardian