Flag of Germany — construction sheet
Own work.  Geometry from description in Order on the German flags

The federal flag consists of three horizontal stripes of equal width, black at the top, red in the middle, gold-colored at the bottom, the ratio of the height to the length of the flag cloth is 3 to 5. The federal flag can also be flown in the form of a banner. The banner consists of three vertical stripes of equal width, black on the left, red in the middle and gold-colored on the right.— English translation of Order on the German flags section I
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