Question 1

How is the number of folds worked out?

Accepted Answer

A sheet of paper is 0.1 mm thick and every fold doubles it, so the height after n folds is 0.1 mm times two to the power n. The answer is the smallest whole number of folds whose stack reaches the target height · mathematically, the ceiling of log base 2 of the height divided by 0.1 mm.

Question 2

Does folding paper 42 times really reach the Moon?

Accepted Answer

In theory, yes. 42 doublings of a 0.1 mm sheet is about 440,000 km, which clears the average Earth-Moon distance of roughly 384,400 km. In practice you cannot fold ordinary paper more than about seven or eight times · the game is about the maths of doubling, not a folding challenge.

Question 3

Are the object heights real?

Accepted Answer

Yes · they are the widely-cited real heights or distances for each object, from a giraffe at about 5.5 m to the edge of space, the Space Station and the Moon. The reveal shows the height it used.

Question 4

Why do such tall things need so few folds?

Accepted Answer

Because doubling is exponential. Ten folds already gives about a metre, twenty folds about a kilometre, thirty folds about 1,000 km · each ten folds multiplies the height roughly a thousandfold, so even huge heights fall within a few dozen folds.

Question 5

Does it work offline?

Accepted Answer

Yes. PlayMemorize is a Progressive Web App, so Paper Folds keeps working without a connection once the page has loaded.