Little triangles, drat them, can have as much/more on the back as the front. I've just never understood how a .25" seam allowance meant you had to add 7/8ths to the desired size!
There are whole disciplines about geometry and folding and such -- a lot of which are used in the space program! I took a lot of math and have played with a lot of origami but the the science is amazing.
https://www.wired.com/2014/09/nasa-i...pired-origami/