Kaprekar Number https://www.mathematische-basteleien.de/kaprekar.htm
Playings with numbers
You may have to repeat this procedure.
Playings with numbers
You may have to repeat this procedure.
Something about cubes
If you have the choice of the following four drawings most people would choose picture
How to fold the Origami-Frog?
I have drawn a line to make this clear. 6 ……
Who am I?
Sometimes I am astonished how many pages have already been assembled.
Tricks with paper strips
I suppose that you have to explain this effect in the same way as a bimetallic bar
About squares
Some nostalgia: I still have a calculator from 1971 (Quelle „Privileg“), which has
Description of a new cube puzzle
The violet triangles are congruent and have the sides sqrt(2)/2*a, sqrt(2)/4*a, and
Puzzles with MacMahon’s Coloured Cubes
Cube and mirror cube have mirror images, for instance Ab and Ba.
How to make a monogram
Many people who he knew have these pictures with their initials in their home.
About spirals
The radii have the ratios 1 : 1.5 : 2 : 2.5 : 3….. Fibonacci Spiral ……