A renowned and also atlethic rope thief arrives at a tower. Inside this tower two ropes with equal length are hanging downwards from the ceiling. The ropes are connected to the ceiling with rings. How can the thief steal as much rope as possible? The only equipment he carries is a knife.

Suppose you have two bottles with equal perimeter, thickness and height. One bottle is cilindrically shaped, the other one has the shape of a rectangular box with a square shaped bottom. In which of the bottles fits more milk?

The last will of a horse breeder is that all his horses are to be given to his three children in the following ratio: 1/2:1/3:1/9. At the moment the horse breeder passed away he owned 17 horses. How could his last will be followed?