If you could fold a piece of paper 42 times, it would reach the moon.

This is possibly one of the most unbelievable facts we’ve ever posted. What you first might think is that this can't possibly be true because the 200 paper stacks sold at stores are only a few centimeters. 

But if you consider how folding paper works, it all makes sense. The moon’s average distance from earth is 384,000 kilometers away. If you take a piece of paper and fold it in half, it would be twice as thick as it was before. One page is about 0.01 centimeters high. 

That means it would take 3,840,000,000,000,000 pages, or 3.8 pentillion pages, to reach the moon- if they were stacked on top of each other. How then, could one piece of paper folded 42 times reach the moon? 

The answer is simple when you consider exponential growth. When you fold a page, it becomes twice as thick as it was before- two pages thick. But when you fold it a second time, it becomes four pages thick because it doubles again. If you fold it a third time, it’s eight pages thick. 

Because paper folding is subject to exponential growth, if you could fold a paper twenty times, it would pass Mt. Everest at 10 kilometers (6.2 miles). With this math, it takes only 42 foldings to reach the moon, and 94 foldings to make something the size of the known visible universe. 

The only problem is you’ll have trouble folding a piece of paper more than a few times. 

(Source)