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Dutch
03-04-2011, 08:32 PM
still do 5. 6, or 7 digit mathematical division on a piece of paper without using a calculator or mechanical figurer?

I could as a grade school kid - I just realized I can no longer even remember how to do it - are kids even being taught real mathematics these days or is it just learning how to do it with a computer or electronic calculator?

gibetheridge
03-04-2011, 08:43 PM
In my head, on a good day. :cool: But, I can't for the life of me remember how to do square roots on paper.

Bobby of Tulsa
03-04-2011, 08:53 PM
Or count money back to a customer?

Dutch
03-04-2011, 08:57 PM
Or count money back to a customer?



dont think they teach that to kids anymore either- thats one thing I can still manage :d

purri
03-04-2011, 09:11 PM
yes.

Paul Pless
03-04-2011, 09:18 PM
http://img.photobucket.com/albums/v54/donnwest/misc/Divided_by_zero.jpgthat sucks

hokiefan
03-04-2011, 09:19 PM
Sure I can. But whats the point? In real life, more than three digits is seldom significant. More often two is enough. If the you have to know the answer to 5 digits to make a decision you're cutting it too close.

And yes they still teach it. But they let kids start to use calculators early enough that they never really get good at it. My opinion, for what its worth.

Cheers,

Bobby

Barry
03-05-2011, 12:44 AM
you mean "gozintas". Sure can. My mom taught me "gozintas" at the kitchen table,( try to hear gozintas with a thick Irish Brogue-Cork Girl ) just as I taught my daughter at the kitchen table.
5 gozinta 20 4times.

Robbie 2
03-05-2011, 03:38 AM
Definitely can.

varadero
03-05-2011, 03:44 AM
The wonderfull thing about kids and an outdated education system is, I am learning it all again for homework. Slightly different system and in Catalan!

John Smith
03-05-2011, 08:45 AM
I believe they still teach this. What they don't seem to teach is how to figure out when one needs to divide, and that's not recent. Several of my supervisors knew how to do the math on paper, but they didn't know, for example, which number to divide by which to get the percentage.

My grandson gave me a Mensa puzzle calendar; 365 puzzles. There are a number of them where I no longer remember how to put things into the proper equation to work out the solution. The only time I've actually run into they types of questions posed are in puzzles.

botebum
03-05-2011, 08:56 AM
I can even do it with negatives. Usually while balancing my checkbook.

Doug

htom
03-05-2011, 09:04 AM
Yes. There's also a pencil and paper cube root method, (http://mathforum.org/library/drmath/view/52605.html) and even (I am surprised and pleased to find this in, and well explained in, Wikipedia) a Shifting nth root algorithm. (http://en.wikipedia.org/wiki/Shifting_nth_root_algorithm)

Rant: Yes, your children should learn how to do these things. Not because calculators can't do it, but because they need to learn to train their brains to do things. Use the calculator to check your results. Sometimes the calculators are wrong. /Rant

wizbang 13
03-05-2011, 10:29 AM
I can still do 30 pushups

Keith Wilson
03-05-2011, 10:55 AM
Sure, no problem. I don't do it voluntarily, though. I don't rip planks with a pit saw either.

I can't do square roots by hand anymore; I once knew how, but all I remember is that it was very very, tedious.

hokiefan
03-05-2011, 01:36 PM
I believe they still teach this. What they don't seem to teach is how to figure out when one needs to divide, and that's not recent. Several of my supervisors knew how to do the math on paper, but they didn't know, for example, which number to divide by which to get the percentage.

My grandson gave me a Mensa puzzle calendar; 365 puzzles. There are a number of them where I no longer remember how to put things into the proper equation to work out the solution. The only time I've actually run into they types of questions posed are in puzzles.

One thing I was thrilled to see was my kid's math teacher taught him that 2/5, 0.4, and 40% were all the same number. Simply stated in different forms. I know a lot of people that never get that concept, and its hugely important if you do anything that uses even a little bit of math.

Cheers,

Bobby

thedutchtouch
03-05-2011, 10:49 PM
yes, although it's much more useful to be able to convert pounds to kg, and scale dimensions in your head etc. which i can also do. its really not that hard. particularly if you have paper.

Michael D. Storey
03-05-2011, 11:28 PM
It remains my opinion that most of the people who have had a patch of rough sledding regarding their real estate in the past three years could have avoided their invitation to the blues with the application of third grade arithmetic. I aint talkin math here, jus arithmetic. It is not that hard to come within a dollar of calculating your monthly P & I in your head. And, you can do it faster than most button pushers.
Do not mistake me. I do own and use calculators, but not at the expense of knowing numbers.

Dutch
03-06-2011, 07:22 AM
It remains my opinion that most of the people who have had a patch of rough sledding regarding their real estate in the past three years could have avoided their invitation to the blues with the application of third grade arithmetic. I aint talkin math here, jus arithmetic. It is not that hard to come within a dollar of calculating your monthly P & I in your head. And, you can do it faster than most button pushers.
Do not mistake me. I do own and use calculators, but not at the expense of knowing numbers.

if the powers that be insist on public education, one of the courses of study that I feel should be taught is personal finance - and no kid should be passed to a higher grade level without a fundamental knowledge of it

paladin
03-06-2011, 07:44 AM
I've mentioned it before...get Dr. Trachtenburgs book on modern mathematics...will teach you ways that you never thought of.

Jachow Trachtenburgs Speed System of Modern Mathematics

You'll be surprised at what you learn and how fast you can move numbers around.

Beowolf
03-06-2011, 09:04 AM
Sure I can. But whats the point? In real life, more than three digits is seldom significant. More often two is enough. If the you have to know the answer to 5 digits to make a decision you're cutting it too close.

And yes they still teach it. But they let kids start to use calculators early enough that they never really get good at it. My opinion, for what its worth.

Cheers,

Bobby

Your opinion is worth its weight in gold in this case.

I started an AP Physics class this year. One of the things that has the students worked up the most is that half the test is multiple choice and that half is calculator free! We're currently working on our multiplication tables on the side.

oznabrag
03-06-2011, 09:07 AM
Can I still?

I used to do a little 'stilling. Anymore, not so much.

Rich VanValkenburg
03-06-2011, 09:42 AM
Yep I can, and btw, what's a calculator? Is that the same thing as a slide rule?

S.V. Airlie
03-06-2011, 09:44 AM
Yep I can, and btw, what's a calculator? Is that the same thing as a slide rule? Slide rule? What's a slide rule? Does it take batteries or can you plug it in somewhere?

pefjr
03-06-2011, 10:00 AM
http://sprott.physics.wisc.edu/pickover/monkey.jpgLet's see now.....hmmmmm....

paladin
03-06-2011, 11:02 AM
My abacus dunno use batteries.
I was once in a class at GWU. Teach said no tests with electronic calculators. Not one person had a slide rule. I got stuck on a math question...a series of calculations where a memory function would have helped. In this class you always dressed "properly" which meant at least a shirt and tie....whether you wore the jacket or not......I suddenly remembered that I did have a calculator...an abacus. My tie clip is a fully functioning silver abacus. Silver frame strung with silver wires and little silver wires bent in circles to replace the beads. Quite an intersting toy, and it works.

Dr.Spoke
03-06-2011, 01:02 PM
Varadero, I hear you... But I do it in swedish.
I still do most arithmetic in my head. I'll back it up with a calculator if I'm unsure... Or a mistake might be expensive!

My Dad tells of one of his maths lecturers who would impress with his mental arithmetic. He would write up a problem, and all would feverishly attack their slide-rules trying to beat him to the answer. My Dad asked how the answer always tallied with the slide-rule (which of course has errors because of it's nature) "Oh!... I CAN do it all from first principles; but for speed, and considering the accuracy needed to build things it is just easier to use logarithmic tables!"
"But you didn't use any tables"
"No... I learnt them by heart!" OMFG!:eek::eek::eek:

BarnacleGrim
03-06-2011, 01:35 PM
I don't get why they use calculators in schools. Anyone can learn to push buttons.

Michael D. Storey
03-06-2011, 01:41 PM
if the powers that be insist on public education, one of the courses of study that I feel should be taught is personal finance - and no kid should be passed to a higher grade level without a fundamental knowledge of it

Thoroughly in line on this one. My mother raised my four brothers and I alone. We all went to school, she paid off the house early and lived well for the remainder of her days. What I know about numbers as it applies to money I learned from Her.

hokiefan
03-06-2011, 01:42 PM
I don't get why they use calculators in schools. Anyone can learn to push buttons.

At a certain point, they start to make a lot of sense. I remember well my high school physics class. Quite often doing the arithmetic took as long or longer than doing the "physics" part of a calculation. On tests, I spent more than 50% of my time doing arithmetic. If I had been able to use a calculator I could have done more physics. Since that is a subject that in my opinion can only be learned by doing problems, doing more physics problems and less arithmetic could have taught me more physics.

Much before the beginning of high school is too early in my opinion.


still do 5. 6, or 7 digit mathematical division on a piece of paper without using a calculator or mechanical figurer?

I could as a grade school kid - I just realized I can no longer even remember how to do it - are kids even being taught real mathematics these days or is it just learning how to do it with a computer or electronic calculator?

One minor point. Arithmetic, that is doing the actual addition, subtraction, multiplication, & division; is only a minor subset of real mathematics. It is an important one, a prerequisite for all of the rest. But it is merely the beginning. I was a mediocre math student until the 8th grade. Because I was always making a silly arithemetic mistake. I knew what I was supposed to do, but would get bored and slip a digit. But in the 8th grade my math teacher started teaching me algebra. From there on I was an excellent math student, at least until I hit differential equations!!! At that point I was no longer excellent, in fact had to work pretty hard to be decent.

Cheers,

Bobby

S.V. Airlie
03-06-2011, 01:43 PM
I basically gave up on math ( using a pencil ) when I walked into a 3rd grader with his father buying a calculator. When I asked the umm 10 yr old why he was buying a calculator in what 3rd grade, he told me that as he had lost hisb and he would be docked one grade by his TEACHER on Monday for not having a replacement.

Bruce Hooke
03-06-2011, 01:48 PM
still do 5. 6, or 7 digit mathematical division on a piece of paper without using a calculator or mechanical figurer?

I could as a grade school kid - I just realized I can no longer even remember how to do it - are kids even being taught real mathematics these days or is it just learning how to do it with a computer or electronic calculator?

If you can do long division on paper with 2 or 3 digit numbers doing it with more digits is just more of the same process. If you are figuring something like 3248 into 6,298,765 then it is going to be a little tedious but the inherent process is no different from figuring out 34 into 118. I still do long division on paper fairly regularly, often when I am in the shop and need to calculate something and don't want to go and get my calculator.

Bruce Hooke
03-06-2011, 01:51 PM
I don't get why they use calculators in schools. Anyone can learn to push buttons.

In addition to Bobby's excellent response, there is also the point that in the work world it is much more common that you will have tools like calculators and spreadsheets handy to do the heavy math work and what you need to learn in school is how to make good use of these tools. Yes, it is important to know arithmetic but it is also important to know how to apply available tools to efficiently solving a problem.

Keith Wilson
03-06-2011, 03:18 PM
If somebody working for me was regularly doing long division on paper instead of using a calculator, I'd have a short but solemn talk with him about not being an idiot on the job.


From there on I was an excellent math student, at least until I hit differential equations!!! At that point I was no longer excellent, in fact had to work pretty hard to be decent.Exactly the same for me. Calculus I understood, even liked. Differential equations, well, I managed to pass, but it all evaporated out of my brain as soon as I walked out of the final.

Michael D. Storey
03-06-2011, 03:26 PM
If arithmetic is only a technique, like drafting, then a calculator or a cad system are tools as much as a drafting table or an adding machine. if there is something more, a thought process, maybe, then we need some other way to teach the thought processing. I rarely keep much in my head that I can readily access, as long as I am not using it often. I mean, I retain the safe combination, instead of relying on my written-down copy, but telephone numbers, appointments, why they are stored electronically.
I do lament that too much of my surrounding is people who say 'I'm not sure,' when what they really mean is, 'I don't have a clue and either do not know how, or have any interest in the thought process necessary to figure it out.'

BarnacleGrim
03-06-2011, 04:29 PM
At a certain point, they start to make a lot of sense. I remember well my high school physics class. Quite often doing the arithmetic took as long or longer than doing the "physics" part of a calculation. On tests, I spent more than 50% of my time doing arithmetic. If I had been able to use a calculator I could have done more physics. Since that is a subject that in my opinion can only be learned by doing problems, doing more physics problems and less arithmetic could have taught me more physics.

Much before the beginning of high school is too early in my opinion.



One minor point. Arithmetic, that is doing the actual addition, subtraction, multiplication, & division; is only a minor subset of real mathematics. It is an important one, a prerequisite for all of the rest. But it is merely the beginning. I was a mediocre math student until the 8th grade. Because I was always making a silly arithemetic mistake. I knew what I was supposed to do, but would get bored and slip a digit. But in the 8th grade my math teacher started teaching me algebra. From there on I was an excellent math student, at least until I hit differential equations!!! At that point I was no longer excellent, in fact had to work pretty hard to be decent.

Cheers,

Bobby
For physics and other applications, sure. But when doing maths for the sake of doing maths, copying decimals off an LCD is not that interesting.

I don't believe arithmetic should be the beginning of learning maths. The first step should be learning number theory, arithmetic will come naturally later on. My first grade teacher taught me you couldn't subtract a larger number from a smaller number, but I was curious to try it on a calculator. When I told her about my discovery she simply said there is no such thing as negative numbers, and to focus on the assigned tasks instead. So I politely threw away my first (correct) deductions on number theory and never really cared about maths again.

Trevor S.
03-06-2011, 04:51 PM
No problem, always a pen or pencil around, not always a calculator.

Flying Orca
03-07-2011, 08:23 AM
I was never taught a manual method for square roots, but I can do most other operations in my head and can handle any practical number of digits you please on paper. Scientific notation helps, of course.

paladin
03-07-2011, 08:49 AM
When I was taking the Westlawn course and Yacht design institute, I made over a dozen forms and graphs for various aspects of the work. I received good comments from Ted Brewer on the development of the tools. It allowed me to finish a set of calculations much faster on a particular hull. I will admit that I may have bypassed directly working with the various formulas, but the intention was to finish the design work that the client was paying for. Now the same work is done by computer, and done automatically as you change parameters. During this same period I was using a HP-45 calculator. They had just come on the market and made my calculations much, much easier and far more accurate. So much so that at one point I received some negative comments from my "instructors". The calculators were not commonly used at that time.
Many designers today do the hull/deck design, spars and bare necessities, then say "use a 12 inch cleat" or "the spreaders should be 32 inches from tip to base" without actually giving detailed drawings of the parts.

David Tabor (sailordave)
03-09-2011, 09:08 AM
SURE. And I can square a number from 1-100 or figure the square root of a number up to 10,000 to w/in 0.1 or 0.2 IN MY HEAD. And yes I've proved it to people.

Sure helps when you have to figure right triangles or just b/c.

gypsie
06-06-2019, 10:20 PM
Knowing how to do long division in ancient Egypt was punishable by death.
Only the high priests were allowed that knowledge.

You need long division to build a pyramid, so the pharaohs needed the high priests, thus their position was assured.

Jimmy W
06-06-2019, 10:38 PM
I just noticed that Hokiefan is no longer shown as banned.

sarnella
06-07-2019, 07:01 AM
Spent over 40 years as a land surveyor - I still have numbers running through my brain 24/7.

Too Little Time
06-07-2019, 07:34 AM
If somebody working for me was regularly doing long division on paper instead of using a calculator, I'd have a short but solemn talk with him about not being an idiot on the job.
I agree with this.

About the only time I do division by hand is after I buy gas for my car. I do in my head, while I am driving.

Garret
06-07-2019, 07:47 AM
I agree with this.

About the only time I do division by hand is after I buy gas for my car. I do in my head, while I am driving.

Not division, but basic addition & subtraction. Back in the 80's I was working as a wholesale salesman for car parts. One of my tasks when visiting my customers was to get any returns, write up a slip for them, then add up their invoices/credits from the last 2 weeks & collect a check for the balance. I traveled with a calculator, as it was often 20-30 invoices/credits that had to be added up.

One day I left the calculator at a customer's & when I got to the next one (50 miles away) I had to add 'em up on paper. Holy carp! I had completely forgotten how to add & subtract. Well - not completely, but I felt like a 3rd grader puzzling over a test as I did it. I decided then & there that the calculator would stay where it was & that I'd add 'em up on paper. After about a half dozen stops, I'd gotten back into the swing of it & it took little more time than using the calculator - but at least my brain was getting a bit of exercise.

Lonely Grandpa
06-07-2019, 06:11 PM
And GPS is also rotting folks brains. Ain't technology wonderful ? I don't make all that many car trips, but I have yet to use a gps for one and in fact have an old style Motorola Barrage flip phone.

https://www.thedrive.com/news/8686/study-using-gps-navigation-switches-off-brain-makes-you-stupid

McMike
06-07-2019, 06:12 PM
So much WBF bilge history on this thread.

Lonely Grandpa
06-07-2019, 06:13 PM
So much WBF bilge history on this thread.

Indeed

McMike
06-07-2019, 06:14 PM
Indeed

Who are you? Certainly not junior.

Lonely Grandpa
06-07-2019, 06:30 PM
Who are you? Certainly not junior.


Why I am Lonely Grandpa. You can ask anyone including my beautiful grand daughters ! :)

McMike
06-07-2019, 06:43 PM
Why I am Lonely Grandpa. You can ask anyone including my beautiful grand daughters ! :)

MmmmmHmmmm

Joe (SoCal)
06-07-2019, 06:46 PM
Heeees Baaaaaaack :D

Its been a while since we’ve had an honest to goodness old school WBF troll. It should be fun until Scot sends him/her/it to Bandcamp :D

Garret
06-07-2019, 07:41 PM
And GPS is also rotting folks brains. Ain't technology wonderful ? I don't make all that many car trips, but I have yet to use a gps for one and in fact have an old style Motorola Barrage flip phone.

https://www.thedrive.com/news/8686/study-using-gps-navigation-switches-off-brain-makes-you-stupid

I will admit to using GPS - it's called being lazy. I can still decipher a map & even know what all those squiggly lines on a topo map mean (something about attitude, right? ;)).

However - seem my post @ #45...

Spin_Drift
06-08-2019, 06:16 AM
Sheesh, I miss old Dutch....

Canoeyawl
06-08-2019, 09:35 AM
http://www.youtube.com/watch?v=3rYoRaxgOE0