Traditional Culture Encyclopedia - Hotel reservation - What is the size of the four-fold page?

What is the size of the four-fold page?

It seems that 40% discount is just a folding method when making printed matter.

Fold a piece of paper in half and then fold it in half, or fold it in half and then fold it in half, which is called 40% discount. Everyone has a different understanding and a different name.

360*2 10 is the size of A4 paper we usually use.