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    people 417 subscribers · A webcomic of romance, sarcasm, math, and language.

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    ISO Paper Size Golden Spiral

    comics.movim.eu / XKCD · Friday, 19 June - 04:00

The ISO 216 standard ratio is cos(45°), but American letter paper is 8.5x11 because it uses radians, and 11/8.5 = pi/4.