A piece of paper is about a tenth of a millimeter thick. The distance between earth and moon is around 400,000 km. How often does a piece of paper have to be folded to reach 400,000 km, bearing in mind that each time the paper is folded it doubles in thickness? While a normal sheet of paper can only be folded seven or eight times, you can still calculate it: After ten folds, there are already 1,024 paper layers, so the initial value increases by a factor of more than 1,000. After 20 folds the tower is 100 m high, after 40 folds 100,000 km! Only 42 folds are needed to get from Earth to the Moon! Mathematicians call such growth "exponential". The paper industry in general is not growing exponentially. But at 2  3% worldwide, it is still a growth industry. Source: Vince Ebert, Focus 17/2017




