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Where Knowledge Junkies Get Their Fix
It’s late at night, you’re working on a report, and you’ve got to sketch some reasonably-to-scale diagrams. But for the life of you, you can’t seem to find a ruler or a yardstick to indicate inches. What to do, what to do?
With two standard sheets of typing paper, you can create a fairly accurate ruler that will measure inches and feet. The question is… how? See if you can figure it out, then visit Page 2 of this post to see if your solution matches ours. Feel free to comment if you know of an easier way, or if you’ve got some other devices that you employ as “practical rulers” when necessary.
Pages: 1 2
I think this post is the highlight of my day
posted by Amy on 4-17-2008 at 9:44 am
There’s a better way — you can get it exactly.
Take the first sheet of paper, fold it the way you originally did (touch one corner to the opposite side. Then, you basically have a triangle on top of a rectangle, as you’ve shown in the picture. The height of the triangle is 8.5, and the weight of the rectangle is 2.5 (adding to the 11 inches in total height). Then, fold the triangle over the rectangle, then fold the remaining smaller triangle back over the rectangle again, and then do that a 3rd time. Each time it takes off 2.5 inches from the 8.5 inch height of the triangle, so when you’re done (assuming you don’t lose any distance during these folds), you’ve measured out exactly one inch (8.5 - 3*2.5 = 1). Now that you’ve measured 1 inch, you can fold the 2nd sheet along its diagonal (which will be longer than 12 inches), and mark off the size of a ruler!
posted by Jason on 4-17-2008 at 9:56 am
A standard piece of paper is 8.5″ x 11″. If you lay down piece A as a portrait (11″ length), then place piece B next to it as a landscape (8″ length), mark off the difference of the lengths (2.5″) on piece A’s side. Then mark off that 2.5″ length on piece B’s shorter side (8.5″), 3 times. You’ll be left with a single inch (1″) at one side of piece B’s shorter side. Use that single inch to mark off the 11 inches on piece A, then you can also switch pieces and mark all 11 inches on piece B. You’re left with 22″ of paper, which you can tape together. If you want, you can get rid of all but an inch of the second sheet of paper, tape that with the first sheet to give you a solid foot.
That was probably too complicated or not very well explained. *shrug*
posted by Ellen on 4-17-2008 at 9:59 am
Bah Jason, 3 minutes faster. Nice job :)
posted by Ellen on 4-17-2008 at 10:00 am
A dollar bill is exactly 6″ long….no math required.
posted by Anne on 4-17-2008 at 10:07 am
A US dollar bill is 6″.
posted by r.e.wolf on 4-17-2008 at 10:09 am
I, like r.e.wolf, use a dollar bill in a pinch. I usually have a bill around and it is good when I am shopping and there is not a sheet of paper around.
posted by JaneM on 4-17-2008 at 10:15 am
If you curl your first finger and use the second section as a guide; it is fairly close to an inch.
posted by Ashley on 4-17-2008 at 10:19 am
From my roofing days, 4 inches is roughly the size of your fist (from index finger to pinky finger) and 8 inches is the span between your thumb and pinky finger when you stretch out your fingers. (This was useful because building code where I worked required a nail to fasten plywood to trusses every 4 inches at the seams and every 8 inches ‘in the field’).
posted by Jaime on 4-17-2008 at 10:26 am
But what if you only have a $5 bill? (Okay, sorry.)
posted by Sandy on 4-17-2008 at 10:28 am
I can do it with one sheet. Fold it into 11 equal-sized sections, then unfold it. The creases are 1 inch apart. I’m not sure why you’d want to make it more complicated.
posted by Craig on 4-17-2008 at 10:40 am
I used Ellen’s method.
Also, how did you figure out the diagonal edge is 12.02″? This has to be something you know before hand as there isn’t a way to determine it.
posted by Florida on 4-17-2008 at 11:11 am
By way of the egyptians:
The length from your knuckle to the edge of your thumb is approximately an inch.
posted by KJ on 4-17-2008 at 11:22 am
Florida:
If you fold the edge over like that, you have a right triangle with two sides, each 8.5″. So, a^2+b^2 = c^2:
sqrt(8.5^2 + 8.5^2) ~= 12.02
*sigh* The beauty of right angles.
posted by Ellen on 4-17-2008 at 11:23 am
Sometimes you overlook the obvious. I was sitting here with a piece of paper trying to figure out a way to use the Pythagorean theorem to figure that out and whole time I was overlooking that the other side would also be 8.5″
Apparently I could only see what I wanted to see.
posted by Florida on 4-17-2008 at 11:30 am
You can easily figure the length of the third side of the triangle, because it is a right triangle. A squared + B squared = C squared. In this case, A and B both are 8.5″. So it ends up being 72.25 + 72.25 = C squared. Little bit of math and you end up with 12.02″ as the longest side.
Pythagoras FTW!
posted by RemedyDev on 4-17-2008 at 11:40 am
Craig,
Your comment reminded me of a challenge we used to try to tackle when in school - folding a piece of paper more than 7 times. It becomes pretty tough. Yet you can implement your suggestion by not making all the folds together. You can first fold the paper in half, open it, fold it this time to bring one edge to the center fold. Repeat by bringing the edge again to the new fold and so on…but the problem is in the end what you’ll get is not 1/11th of the length. After 6 folds using above method, you’ll get 1/12th of the 11 inches = 0.9something.
But you could tear the paper (bottom part of figure 2 on next page) and get a 12.01 square and apply the above method and get 1.000something.
posted by septer on 4-17-2008 at 12:04 pm
well no i am wrong in my explanation above. folding 3 times will give you 1/8th (1/8th of 12.01 ) and 4 times will give you 1/16th.
Also you won’t get a 12.01 square…you’ll get 8.5 inch square if you tear the bottom part.
posted by septer on 4-17-2008 at 12:10 pm
aargh…ignore the ‘(1/8thof 12.01)’
posted by septer on 4-17-2008 at 12:12 pm
For some reason, I can’t see a way to get to page two from the front page. But when I went to the comments, I can see “Pages: 1 2″.
I could’ve figured this one out really fast IF I had known the dimensions of a standard sheet. However, I know my thumb is exactly two inches -one inch to each knuckle.
posted by Miss Cellania on 4-17-2008 at 12:12 pm
Since I don’t often keep cash around, I can’t use the dollar bill method. I guess I could use the folding methods, but I keep a link in my favorites to “printable rulers.” It prints out a perfect ruler on standard sheets of paper.
Or, I use my hand. Spanned open from pinky to thumb, it’s about 8 inches. Or my arm, from elbow to wrist, is close enough to a foot for estimation. Wouldn’t really work to draw stuff to scale, though.
posted by Jeremy on 4-17-2008 at 12:28 pm
Hah, gotta be careful with your method, Jaime. My fist’s less than three inches across at the knuckles, and my whole hand spread out is less than 6.
So I’d have some wonky roofs.
posted by Aemi on 4-17-2008 at 6:03 pm
Some of you people are really…MATHY…
posted by Meri on 4-17-2008 at 11:15 pm
I folded one sheet in half top to bottom, this made an edge of 5 1/2″. I set it along the short side of the unfolded sheet and got a 3″ mark. I then unfolded the first sheet and marked every 3″ along the 11″ side of the first sheet. I was left with a 2″ mark which I measured from my 3″ mark to produce a 1″ mark and filled in the rest of the inch marks on the original sheet.
posted by Bill on 4-18-2008 at 8:38 am
that is a relly cool way of doing it, I would have never thought of that. I like Craigs suggestion but it would be a bit tricky trying to fold a piece of paper into 11 equal pieces…….
posted by sherbet on 4-18-2008 at 4:22 pm
Tsk, tsk — too complicated, all of you. Here’s the thing: lay the two sheets next to each other, so that together they measure 17″ (8.5×2). Then mark where one end of that length begins, pick up that page, and lay it on top horizontally. The difference in length (17-11) is six inches. Double it to make a ruler.
posted by shel on 7-5-2008 at 4:57 pm