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The Logic Behind Metric Paper Sizes

Oily Pakora writes "Those of us in the United States are so used to our Letter and Legal paper sizes. We've seen the A4 paper size option in our printer trays and in printer preference menus. Metric sizes used almost everywhere in the world, save for the US and Canada. Here is an interesting article that discusses all of the aspects of metric paper. For those who enjoy a bit of math, did you know that in the Metric paper system, the height-to-width ratio of all pages is the square root of 2? This means that you can place two sheets of A4 side-by-side and they will equal an A3 sheet exactly, and two sheets of A3 will equal an A2."

16 of 1,461 comments (clear)

  1. Side-by-sideness by TyrelHaveman · · Score: 5, Informative

    You can also put two 8.5x11 (Letter) sheets of paper side by side and it equals an 11x17 (Tabloid) sheet of paper...

    1. Re:Side-by-sideness by SSpade · · Score: 5, Informative

      But 11x17 is not the same shape as 8 1/2x11.

      That's the real beauty of A4/A3 etc. All the sizes in a given series (A00, A0, A1, A2, A3, A4, A5... or B1, B2, B3...) are the same shape.

      So you can photocopy an A4 document onto A3 paper expanding it by the right proportion and it'll fit perfectly. And you can copy two A4 documents onto A3 paper and it'll fit perfectly. Or use psnup to put A4 formatted documents reduced to 2-up on A4 paper with no wasted space.

      Try that with letter or legal size....

    2. Re:Side-by-sideness by barawn · · Score: 4, Informative

      When you discuss the advantages of metric, it really is about convenience[1]. There's nothing that you can do with metric that you can't with the English system; it is just, generally, more difficult to do with the English system. If you don't care about convenience, and you live in the USA, then you probably don't have any reason to use metric.

      That's not quite true - one of the reasons that the Imperial system is moderately convenient for building is that base 12 is divisible by 2,3,4 and 6, so you'll encounter less rounding error if you need to split things up into common numbers. Base 10 is only divisible by 2 and 5. (Incidentally, this is of course why one of the older civilizations used base 60 - it's divisible by 2, 3, 4, 5, and 6, and it's the reason we have 60 seconds in a minute, 60 minutes in an hour).

      So, for instance, if you want to break a 1' object into thirds, you can do it exactly. Try doing it with meters - it's 33 and a third centimeters. Most people would say "screw it, it's 333 mm" - but if you now take those "1/3 m" sticks and put 300 of them end to end, you don't have 100 m - you have 99.9 m, and you're a full ten centimeters short. In imperial, 1/3 of a yard is 1 foot. No rounding errors.

      There really *are* advantages to the Imperial system - most people, however, simply assume that Imperial sucks and leave it at that.

      Metric paper, however, is better designed than US. Being able to print 2 A4 on 1 without much work really kicks.

  2. Re:Drugs teach American kids the metric system. by Anonymous Coward · · Score: 4, Informative

    That joke is in the title. From the "forty-rods-to-the-hogshead department."

  3. More usefully... by MartinG · · Score: 4, Informative

    you can place two sheets of A4 side-by-side and they will equal an A3 sheet exactly,

    More usefully, you can fold an a4 piece of paper in half and it will fit nicely in an a5 envelope.

    --
    -- MartinG To mail me: echo kewyjlcxyzvjfxbqwh | tr bcefhjklqvwxyz .@adgimnoprstu
  4. Do the math, indeed by lambent · · Score: 4, Informative

    Square milimeters of paper:

    Letter: 60322.46 mm^2 (215.9mm x 279.4mm)

    A4: 62370 mm^2 (210mm × 297mm)

    A4 - Letter = 2047.54, or about 3 and 3/16 square inches.

    A4 is bigger.

  5. Re:Drugs teach American kids the metric system. by compro01 · · Score: 5, Informative

    if i remember corectly a "hogshead" is 63 gallons.

    and a rod is 5.5 yards or 16.5 feets so....

    damn your car is a gas guzzeler!

    504 gallons to go 1 mile!

    --
    upon the advice of my lawyer, i have no sig at this time
  6. Re:Yet another reason for the US to switch to metr by SkankhodBeeblebrox · · Score: 5, Informative
    Your government did try to switch over, not once, not twice, but three times! (with limited success, according to the 2nd link)

    Also according to that 2nd link,
    "Federal agencies were required by this legislation, with certain exceptions, to use the metric system in their procurement, grants and other business-related activities by the end of 1992. "


    Not sure what that means to a typical U.S. Citizen, but it appears the U.S. will be metric someday :)
  7. Re:Oooo.... root 2! by Rupert · · Score: 4, Informative
    Those aren't the same shape.
    17 / 11 = 1.55
    11 / 8.5 = 1.29
    A4 paper is twice the size and the same shape as A5. A3 is twice the size and the same shape as A4. It goes up to A0, which is (ooh) 16 times bigger than A4.
    --

    --
    E_NOSIG
  8. Re:2 x A4 = A3 by hpa · · Score: 4, Informative

    A0 paper is one square meter.

    A4 paper is 2^-4 = 1/16 square meter.

  9. Re:Yet another reason for the US to switch to metr by fireduck · · Score: 4, Informative

    except that the US apparently sanctioned the metric system in 1886, and the American Bureau of Standards made the metric system it's standard in 1964. (nice timeline here ). There've been various attempts to further adopt in more recent history, but basically the US doesn't want to change. The metric system is nonexistant as far as general use is concerned. The only "off the top of my head" metric use I can think of are 2 L bottles of coke. nothing else gets metric treatment.

  10. Re:2 x A4 = A3 by chris_mahan · · Score: 5, Informative

    a square meter. a square meter is the base of a cube meter. The cube meter is the volume of one ton of fresh water at sea level at the equator at zero degrees Celcius. 1 ton is 1000 kilo gram. each kilo gram is thus 10cm*10cm*10cm, which happens to also be a liter. 1 gram is 1 millionth of a ton, of 1cm*1cm*1cm. so if a bottle of water is 1000 grams (1 kilo gram), it is also 1 liter. So now I know the volume, the weight, and the measurement of the container. Pretty nifty no?
    Density is expressed in a ratio from fresh water at zero degrees at sea level at the equator. Let's say the density of velveta cheese is 1.001. With this, I could tell you the size of a kilo of velveeta, and how large a container to use, and thus how much paper to use to wrap it in. Then I could express this in how many per A0, A1, or A2, since they are derived from the meter. Get it?

    Class dismissed.

    --

    "Piter, too, is dead."

  11. Re:A complex way to point out simplity. by Tony-A · · Score: 5, Informative

    Gee, I just learned that if you take a sheet of A3 and cut it in half, that's A4.

    If you take a D-size sheet of drafting paper,
    cut into halves, you have two sheets of C-size drafting paper
    cut into quarters, you have four sheets of B-size drafting paper, aka quarto
    cut into eight pieces, you have eight sheet of A-size, aka letter, aka octavo.

    The metric sizes preserve aspect ratio, the english sizes do not.

  12. Not English by Gonoff · · Score: 4, Informative

    The metric sizes preserve aspect ratio, the english sizes do not

    The sizes of paper you use are not English. In England, and the rest of this country, we use the international standard that includes A4. I suspect that you can buy other standards but I have no idea whatI would have to do if I needed "letter" or "legal" size paper.

    --
    I'll see your Constitution and raise you a Queen.
    1. Re:Not English by Spudley · · Score: 4, Informative

      Not only do we not use 'English' paper sizes in England, but we never used them.

      Before we adopted A4 as our standard printer paper, typing paper was generally sold here in the wonderfully named Foolscap page size.

      It was only a few years ago that stationery shops in England stopped selling Foolscap paper... around about the same time that Inkjet printers finally killed the market for dot matrix.

      It was standardised printer models that killed off the Foolscap standard.

      --
      (Spudley Strikes Again!)
  13. Re:A complex way to point out simplity. by ZeLonewolf · · Score: 5, Informative

    No, but since you ask:

    The number is the measurement below the bust.

    an A-cup is a 1-inch difference between the measurement below the bust versus around the bust.
    B-cup is 2 inches, C-cup is 3 inches, etc.
    DD is the same as E, DDD is the same as EE which is the same as F. This holds valid through an H cup. After that, the interval is 2 inches, with the doubled letter being the in-between value.
    This, H-cup is 8", and I-cup is 10", and a 9" difference would be an HH-cup.

    The largest bra size manufactured without a special order is a size 60N.

    --
    "If at first you don't succeed, lower your standards."