Solve Multiplication Problems by Drawing Lines

Submitted by: buddy 10 years ago in Science

Pretty cool trick.
There are 94 comments:
Female 1,412
hmm. seems fastyer to just multiply. cool trick, though. who thinks up this stuff? like, "hey. im gonna add lines now"
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Female 416
COOL! my b*tch of a teacher would`nt like it. I should totally try that!
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Female 17
Interesting and creative, if not a bit regressive.
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Male 4
That was pretty cool and I can see how that would make Math more interesting to someone who hates it but it`s easier to just do it in your head.
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Female 690
I don`t think I need to get any slower doing maths and if I couldn`t use a calculator I would drop math.
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Male 870
Everyone asking how it works: read the comments on the first page. It`s not that amazing, really.
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Female 209
umm...i think i`ll keep my graphing calculator thanks
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Female 943
woahh
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Female 368
thats crazy that it works but its still faster to do longhand....might be easier for kids though.
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Female 14
a little confusing but...xD
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Male 5
How in the hell does that work!?
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Male 184
SICK!
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Male 70
this takes up too much space on the paper anyways. USE A CALCULATOR
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Female 35
WTF umm yea kinda dont get it
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Female 130
That`s confusing! I tried it and I don`t get it. Maybe I`ll send it to my math teacher... nah. I think that person is from France. THey write their nines like a lower case English "G".
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Female 228
bet that only works for certain numbers... ): o well we use calculators for everything anyways ^.^
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Male 338
This method is stupid and impractical. Unless you have loads of time on your hands.
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Female 419
I`d use that if I could remember it, I`m not the brightest at maths lol
I use the box method anyway but then it takes ages to add them all up at the end.
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Male 55
OK... Who the hell still takes math tests that test your multiplication skills??? Are you guys like 7?
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Male 643
Math sucks.
Calculators pwn.
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Female 411
wowo. yes. wowo.
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Male 957
pretty neat.
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Female 670
:) This... is awesome.
When my dad wakes up, I`m showing it to him. He`ll enjoy it. Silly little math freak.
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Male 870
Manticore, I don`t know what you`re talking about this working with other base systems. This is exactly the same as multiplying with digits using pencil and paper. That also works with other base systems, but you have to remember that 3*7=16, (e.g.) instead of 21, and so forth. You have to remember that using this system also, so I don`t see how it helps at all.
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Male 2,605
Masticore, how ever did you calculate logarithms without a calculator? Did you convert them to exponential functions first or what?
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Male 141
I dont belive they found another way... seems pretty cool. now i can teach my math teacher another method lol
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Female 536
Yeah, I mean, this trick is the COOLEST. I mean, yeah, we can all use calcualters, but what if you don`t have one? What if you can`t use one cause you`re taking a test? This trick would be so easy. ANd I like what dracokain said about the showing the work thing lol. Next time my teacher asks me to show my work I`m doing that lol
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Male 109
Calculators are the worst thing to ever happen to math education.

Seriously. The best thing I ever did for getting good at math was lose my calculator early on in pre-calculus and not tell my parents.

And the lines would get faster in a hurry if you drew them faster. Too bad that long division is faster unless you are slow at multiplying by 7, 8, or 9, in which case you have more lines to draw.

Best part I can see about this is that it works with other base systems - suppose you want to multiply 6`b011101 by 6`b111001. Or 8`h1A by 8`h06. Could help.

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Female 695
looks like more work to do
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Female 90
ummmm hone get a calculator my brain hurts now X-(
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Female 266
I don`t do drawing and counting lines. It isn`t my thing.

Normally I just strain to figure it out until I break down and do that damned lattice method of multiplication

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Male 469
Hmm. Nifty. I`ve never seen anything like that before.

I imagine it has some practical application, though. Might be a fun project.

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Female 797
nicole, I did too. I don`t need this information
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Female 1,596
ZOMG It`s simpler now!!! Thanks!!
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Female 2,552
I did this in 5th grade...
I`m not kidding.
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Female 878
> - <
But what if there wasa 9 hmmm?
I`d rather use a calculator
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Male 2,510
who writes a 9 like that...?
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Male 4
it might look easy for 123 x 321, but imagine doing it with 948 x 769 or for that mather even 49 x 97 would take ages, having 81 intersections at one place, 63 at another, then 36 and finally 28. A lot of counting then.
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Female 106
blahh.. looks too long! how bout uhmm.. use a calculator! :DD
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Female 40
i dont get it
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Male 556
ummm...id rather use a calculator or write it out
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Male 924
too true NyQ i kept forgettin things like that but then i got dr kawashimas brain training and it really helps

this is quite a good method if your bored and have time, its not faster but it would be fun to see what the teacher did when they saw this

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Male 375
and long multiplication could still leave the mathematically-inept with a problem...what if they can`t remember that 7x8 is 56?

these lines sure would solve that problem

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Male 561
more easier just to do it
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Male 11,739
Yeah because this is SO much better than actually doing the math. Creative I guess but I`d rather not spend all of that extra time figuring it out.
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Female 1,398
lame, much easier to just figure it out I say.
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Female 268
that was cool but it is easier just solving it ther normal way.
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Female 1,065
I..still don`t get it o_o;
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Male 68
That`s the most useless thing I`ve ever seen. How is that any faster than doing it the old fashioned way? Not only that, who in their right mind does math without a calculator these days anyway?

/One...two...TWO boobies! Ah ah ah!!!

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Male 1,929
There are loads of easier ways to do this. Longhand for starters.
My year 5 teacher taught me a cool way which was in escence long division, but did in little steps and add it up all in your head. Which is why i can do 1283*134 mentally in 2 minutes when i dont have stuff to write on! lol
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Female 187
^^lol tallun.if i was in school still or studying a college course that required the use of maths, i`d do it too.was thinking the same thing while watching it and was like "wonder what the teacher woulda done if i starting doing that all over my papers?"
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Male 22
I`m so gonna do that on the next math test. I can imagine the teacher`s expression.
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Female 351
WOW!!! that is so cool!
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Male 38
Thats kewl! Not that it`s faster, but sometimes i`m too tired for the real way/ calculators not allowed.
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Male 35
Its KINDA similar to a method called "Napiers Bones" or "Napier`s Rods" if anyones ever heard of that.
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Male 60
Pretty cool trick
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Male 2,513
CALC`S ARE AWESOME
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Female 600
I think I`ll just stick with my calculator. It hasn`t failed me yet. Stupid lines....
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Male 266
It would be fun to do in math class when your teacher asks you to show you work and when you turn it in she would be like omg wtf dood?
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Male 25
thats cool and all, but im good with a calculator. nice trick tho
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Female 172
yes! its much easier to count little dots!!

but it is cool in theory. i dont think i`ll ever use it tho.

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Female 873
I used Napia`s Bones at skool simular to tht.. cant really explain it perhaps i can find a pic to show ya..
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Male 1,217
spoonfork: the answer is the people who live on the internet.

WOW this is amazing.

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Male 2,057
i wish i still did maths in the sixth form now. Actually, no i dont!
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Male 2,057
WOW! who found that out?
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Male 1,725
this will realy help me in skool now
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Male 2,605
So they are accepting math links? Then why not the Ten Commandments of Math I submitted a bit ago? Hum.

I suppose this method would help the visual learners, but I`m a math tutor at my local college and wouldn`t recommend this trick to anyone. It`s time consuming and requires more space on the paper. Oh, and some of you may be forgetting that in lower level math classes, calculators are not permitted.

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Male 732
Ooooooohh! Nice patterns!!!
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Male 163
Man, some of you guys just completely missed the point. Of course a calculator is better. This is not supposed to be the solution for failure in math. It`s supposed to be a cool trick. And it is. And YouG, thanks for the zero tip, was battling it that one.
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Male 2,519
Saw it first on digg. By the way, if it`s 0, then draw an imaginary line.
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Male 1,265
Personally I always preferred stones in the dirt.
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Female 146
i love math!

me = nerd... i know...

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Male 128
lame
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Male 136
I got bored watching that. yeah just use a calculater. save u loads more time.
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Female 665
OR! you could use what us modern day people call.... a calculator!!! *gasp*
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Male 9
thats pretty cool, but its like taking the scenic route when going somewhere, you know it takes longer but you want to try something different and it will increase your driving skills
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Male 266
yea, lets take 5 steps back, hell, lets just use abacuses
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Female 157
that is a really neat trick, whoever figured that one out is awesome! But I still like my calculator best ^^
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Male 651
Seems like a huge waste of time. It`s not that hard to multiply several numbers. Just use your fingers if you`re stuck.
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Male 256
too f|_|cking cool, that`unna make math soo much easier.
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Male 870
Of course.
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Male 713
hahha not bad, but wouldnt it be easier to use the regular long multiplication method
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Male 1,385
neat trick, just did 27 x 156 and got 4212 using lines, checked it with a calc and it was right. so then i did it long hand and found that to be alot quicker than the lines
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Male 2,567
As borat would have said it : wowoweewah!
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Male 908
O_o
my brainnnnn
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Male 870
*continuing* That is why the diagonal lines match up the decimal places: imagine you start drawing the diagonal line from the top. You go down one and to the left one: going down reduces the place, but going to the left increases the place, so together they cancel out, and you are dealing with the same decimal place. (You can start from the bottom and go up and to the right--same thing).
At the end, he carries whatever digits he needs to. It could get more complicated than he made it, with multiple carries, but that works the same as carrying in the standard way of doing these things.
This is really the same thing as doing the multiplication the regular way (except you don`t need a multiplication table), so it does work for everything, 72tour. The only thing you have to add to take care of all the cases, is that he didn`t show how to write a zero. Suppose we make zero a dotted line, and don`t count intersections with dotted lines. Then it works for everything.
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Male 943
wow, my math skills just got a whole lot better
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Male 870
Clever trick. Shinu, this is why it works:
The spaced out lines correspond to ones, tens, hundreds, etc., just like the numbers in the decimal system (321=3 hundreds, 2 tens, 1 one--same for the 3,2,1 lines). There are at most two sets of each type of line, one for each number. That makes it possible to do the multiplication graphically: e.g 3x2 lines will intersect each other 6 times--you can see that. Where the lines intersect it`s like multiplying one by the other: e.g., if the ten line intersects a hundred line, you`re counting thousands. So the intersection of 3 hundreds and 2 tens, or 2 hundreds and 3 tens gets you 6 thousands.
Since the lines are drawn in order, which place is which is also in order: e.g. at the bottom right, you are multiplying ones by ones, so you are counting ones. If you go one up or one to the left, you are multiplying ones by tens, so you are counting tens. Basically, every step up or to the left, moves the decimal place one to the right. That is wh
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Male 17
its really not that cool, when you cross 2 lines with three lines you get 6 dots, and so on, he`s still doing each individual step but he`s just able to visualize it. it does take care of the values of each digit nicely, though.
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Male 1,265
WTF? Who figures this crap out?
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Female 27
Pretty cool - but it takes way longer than just writing it out. :P
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Male 222
Wacko stuff right there. Not sure it`d work for everything, only certain problems.
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Male 1,386
yay my first first comment ever!!! good for a 201st post. and thats amazing that that works. its kinda confusing, but wow.
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Male 10,115
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