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Oh well!<\/p>\n<h2 id=\"problem-statement\">Problem statement<a href=\"#problem-statement\" class=\"toc-anchor after\" data-anchor-icon=\"#\" aria-label=\"Anchor\"><\/a><\/h2>\n<p>Now the challenge is the following: I am going to ask you to write the letters <code>ABCDEFGH<\/code> in the rectangles you created and I need you to fold the piece of paper in such a way that,<\/p>\n<ul><li>the eight small rectangles are on top of each other, making a stack of eight squares of paper;<\/li>\n<li>if you go through the rectangles one at a time, the letters show up in order.<\/li>\n<\/ul><p>The only restriction is that you can't cut your sheet of paper! The point is to <em>fold it<\/em>, not to take a pair of scissors and cut the paper along the creases.<\/p>\n<p>There are going to be three levels, corresponding to three different letter layouts in the rectangles you creased. Start with level 1, write down the letters and try to fold the paper correctly. When you get it right, erase the letters and write down the letters for level 2, and then for level 3! Good luck!<\/p>\n<h3 id=\"level-1\">Level 1<a href=\"#level-1\" class=\"toc-anchor after\" data-anchor-icon=\"#\" aria-label=\"Anchor\"><\/a><\/h3>\n<figure class=\"image-caption\"><img title=\"ADEH \/ BCFG\" alt=\"Left to right, top to bottom the letters are ADEH \/ BCFG\" src=\"\/user\/pages\/02.blog\/03.problems\/p019-fold-the-alphabet\/lvl1.webp\"><figcaption class=\"\">ADEH \/ BCFG<\/figcaption><\/figure><h3 id=\"level-2\">Level 2<a href=\"#level-2\" class=\"toc-anchor after\" data-anchor-icon=\"#\" aria-label=\"Anchor\"><\/a><\/h3>\n<figure class=\"image-caption\"><img title=\"AHGD \/ BCFE\" alt=\"Left to right, top to bottom the letters are AHGD \/ BCFE\" src=\"\/user\/pages\/02.blog\/03.problems\/p019-fold-the-alphabet\/lvl2.webp\"><figcaption class=\"\">AHGD \/ BCFE<\/figcaption><\/figure><h3 id=\"level-3\">Level 3<a href=\"#level-3\" class=\"toc-anchor after\" data-anchor-icon=\"#\" aria-label=\"Anchor\"><\/a><\/h3>\n<figure class=\"image-caption\"><img title=\"AHBG \/ DECF\" alt=\"Left to right, top to bottom the letters are AHBG \/ DECF\" src=\"\/user\/pages\/02.blog\/03.problems\/p019-fold-the-alphabet\/lvl3.webp\"><figcaption class=\"\">AHBG \/ DECF<\/figcaption><\/figure><div class=\"notices blue\">\n<p>Give it some thought... and most important of all, try it for real with an actual piece of paper! Let me know how it went in the comment section below ;)<\/p>\n<\/div>\n<div class=\"notices green\">\n<p><strong>Tip<\/strong>: if you are having a hard time keeping track of which rectangle is which, consider also writing the letters on the back of the sheet of paper, but be sure to <strong>label them correctly<\/strong>; a single rectangle should have the <strong>same<\/strong> letter front and back!<\/p>\n<\/div>\n<div class=\"notices green\">\n<p><strong>Tip<\/strong>: if the paper is too strong and you are having a hard time manipulating it, consider scrambling it and then flattening again before continuing.<\/p>\n<\/div>\n<p>I heard of these from a friend and he learned about this problem by watching <a href=\"https:\/\/www.youtube.com\/watch?v=GpClxF41ugg\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" class=\"external-link no-image\">this YouTube video<\/a>.<\/p>\n<h2 id=\"solution\">Solution<a href=\"#solution\" class=\"toc-anchor after\" data-anchor-icon=\"#\" aria-label=\"Anchor\"><\/a><\/h2>\n<h3 id=\"level-1-1\">Level 1<a href=\"#level-1-1\" class=\"toc-anchor after\" data-anchor-icon=\"#\" aria-label=\"Anchor\"><\/a><\/h3>\n<p>For this one, all you had to do was fold the paper along the horizontal line and then fold the resulting piece of paper like a concertina.<\/p>\n<h3 id=\"level-2-1\">Level 2<a href=\"#level-2-1\" class=\"toc-anchor after\" data-anchor-icon=\"#\" aria-label=\"Anchor\"><\/a><\/h3>\n<p>This one is much harder to explain in words so I made some more drawings and made some markings on the sheet of paper:<\/p>\n<p><img alt=\"Level 2 sheet of paper with some markings\" src=\"\/user\/pages\/02.blog\/03.problems\/p019-fold-the-alphabet\/lvl2-faceA-sol.webp\"><\/p>\n<p>Now if you...<\/p>","summary":"Help me fold this piece of paper so that the alphabet comes in order!","date_modified":"2025-07-23T16:49:02+02:00","tags":["geometry","origami","mathematics"],"image":"\/user\/pages\/02.blog\/03.problems\/p019-fold-the-alphabet\/aaa.jpg"}]}
