Metric paper which always has the same ratio of dimensions when folded in half that being 1/sqrt(2). How was the logic behind this derived?

Question

Metric paper which always has the same ratio of dimensions when folded in half that being 1/sqrt(2). How was the logic behind this derived?

In: Mathematics

Answer 1

It’s not exactly difficult to think that the next size down should be one page folded in half, and the next size up should be too pages side by side.

The more baffling thing is that there are entire systems of paper sizes which don’t do this extremely obvious thing. Metric paper’s system has existed since 1786, the US has had long enough to switch to it.