Calculators Vs. mental

[maple flats]

While math was always my strong point (until calculus that is) I remember well one professor I had in college. He taught business math.
Back in the 60's, when I was in college (business management major), calculators were just coming into their own. The students all had one (back when the basic calculator cost about $40-50). In that class the professor told us we were wasting time using one of those gadgets. On several occasions he had a member of the class write a long column of 4 digit numbers on the board while the class and the professor were focused in an other direction. The list was on the board but was blocked from view by both students and the prof. Then he challenged us to add the column using our calculators while he did it in his head. He wrote his answer on the board and covered it so we could not see. When we were ready he asked for the answers, which were many, then he showed his answer. He never missed, was always done long before we were and as I said, we came up with lots of answers.
He told us to do it in our heads, like he did. He said to just look at the 1st number (all 4 digits). He told us not to say the number, our mind knew the number, then look at the next line. Don't say the number just look, a total will appear. Do this for each line until you have the final total.
He never missed, over half of use were wrong each time.
I tried but never mastered this method.
While our competitions were always 4 digit numbers, he demoed at times with other length numbers and varied length numbers. His system was impressive.
At my age, I can't even do that with single digit numbers without saying the numbers in my mind, must be I failed that aspect (however I got 4 A's in 4 semesters with him).
Try it!

[Magicman]

I had a math teacher that could do that, but he would not show us how he did it, just laughed.  I did not view him as a very good teacher.  Maybe we did not have the gift to do it or could not have learned, but as a teacher, he should have tried.

[red oaks lumber]

life is enough of a struggle, i'm not adding to the struggle man invented the calculator for a reason , so red oaks could use one. :D

[POSTON WIDEHEAD]

life is enough of a struggle, i'm not adding to the struggle man invented the calculator for a reason , so red oaks could use one. :D

:D :D :D

[dgdrls]

In Dr. Elgin's article you could eliminate the word "Surveying" and it still generally applies
I had to learn/relearn many of these concepts when I was
earning my Land Survey Degree in the early/mid '80's

I used his guidance with my 2 children when they were in High School.
Both my children took 4 years of H.S. math to make darn sure the
foundation was study and could handle the load of advanced math/Calculus
in college if they needed it.

http://www.amerisurv.com/PDF/TheAmericanSurveyor_Elgin-DemiseOfMath_May2007.pdf

DGDrls

[drobertson]

I will never forget My ole high school algebra teacher, Mr. Cheek, very few calculators in his class. all word problems,  and at the beginning of every test he would chalk on the board, " Time, Patience, and Endurance"
then below he would write out the problems, all 5 of them, when at the end of the board he would move back, erase the first one and continue,  till all five were shown,  not sure why I saying this, I guess Mr. Cheek left a mark on me.     david

[Ron Wenrich]

Sort of like Evelyn Woods speed reading.  You don't need to say every word in your head.  I used to do a lot of math in my head, especially when sawing.

We didn't have handheld calculators in college.  I bought one in the '70s and it cost nearly a week's pay.  My father-in-law worked for Hamilton Watch.  When I got married, he brought a prototype of a calculator on a watch.  That was in 1976.  He had to sign the watch out, and it was valued in the thousands of dollars.  Only a few in existence. 

I took a 1 credit course in computer programming, figuring I'd never work for an outfit that was big enough to afford a computer.  Everything was put on punch cards. 

How things have changed.

[sandhills]

I spent 3 hours a day with my algebra II teacher in highschool, algebra class, study hall, and one class I was suppose to  be student teaching in  :.  I really stink at math but he always knew when to step in and help me out and when to let me figure it out on my own, I was one of the few that did but I always really liked him.  He also taught computer science, back then it was Apple IIe's and he always said "you need to learn this, pretty soon the world will be run with these", who'd a thunk it  :D.

[Dave Shepard]

A friend of mine once said that the only good to come from the space program was the pocket calculator. I guess he doesn't think too much of the space program. :D

[samandothers]

In 4th grade I can remember acting the class clown.   8)    The math teacher's punishment for goofing off was to assign us to write out and turn into her the multiplication tables 1 to 12.   I think I wrote so many it helped to drill multiplication into my head!
I must admit my tackle box/tool box I use with the mill has a tap measure, face mask, ear plugs, pliers and a small solar powered calculator.

[dgdrls]

A friend of mine once said that the only good to come from the space program was the pocket calculator. I guess he doesn't think too much of the space program. :D

And the Fisher Space Pen ;)

DGDrls

[jueston]

A friend of mine once said that the only good to come from the space program was the pocket calculator. I guess he doesn't think too much of the space program. :D

And the Fisher Space Pen ;)

DGDrls

the Americans spent millions of dollars inventing a new type of pen that works in space, the Russians brought pencils with them....    :D

but as for math, i watched a documentary about Japanese schools, they were going back to using the abacus to teach addition, after a while the kids said they could see and use the abacus in there mind even when they didn't have one in front of them. to demonstrate this, the teacher stood at the front of the class and listed 10 numbers in varying length and the second the teacher finished saying the last number the kids would write down there answer. not 100% of them were correct but it was still amazing, i couldn't keep up after the first few numbers....

whenever i see someone who has an amazing skill like adding in there head, i am impressed but i often wonder weather it actually gives them an advantage in life. how often does the speed in which you can add numbers really come into play in your life? for me, accuracy is FAR more important than speed, and if i could add numbers super fast, i would still need to double check it 2 more times on a calculator anyways.

[Cedarman]

I have saved a fair amount of money by checking fast food, restaurant and other bills.  I may not add to the cent, but I have a real good idea of what the bill ought to be.  4 out of 4 times the bill is not in my favor.

[red oaks lumber]

cedarman
are you saying the cash register is adding wrong? or the highly paid( ) employee entering it wrong?