I just had an experience that just blew me away. I purchased a pack of cigarettes from a store in a nearby town. I was told the price was $7.85. I presented a ten dollar bill. The girl at the cash register punched in the 10, and and I received $2.07 in change.
Now I was expecting $2.15 thankyou very much. When I asked her to review the exchange she mumbled something about taxes which doesn’t even come close to explaining an 8 cent discrepency. Finally she pointed out the display on the cash register as if that was the final word.
I politely reviewed with her the purchase figure, the total cash presented and implored her to recognize that the cash register figure was in error. Finally she pulled out a calculator and to her amazement she had to conclude I was right.
Now I give myself some credit for a sense of a person’s intelligence and this girl was no dumb blonde. I can only conclude that this latest generation was raised on calculators and as a result have no intuitive ability to recognize proper outcomes of even the simplest arithmetic. Both my daughters will give me a blank stare if I challenge them with questions pertaining to the 12 times table.
I think calculators need to be banned from the classroom until at least grade 9. I can’t believe our younger generation can take us to new heights of achievement when they need a calculator to determine the difference between 7 and 15 cents.
I think they should be completely banned unless absolutely required for some kind of complex graphing. You would be amazed at the number of people who can’t add or subtract, let alone multiply or divide, in their head. It’s really despicable.
I agree that calculators should be banned at the elementary school level, and only allowed in jr. high/middle school when students are beginning to learn basic algebra.
A person should have enough of a grasp of basic math to know that 100 - 85 = 15.
I’m a former craps dealer, and learned through having my cerebral cortex pounded bloody on a daily basis to do some fairly complex math operations in my head, but I don’t think I would ever have survived my first few months of dealing if I didn’t have a grasp of basic addition, subtraction, multiplication and division. I often had to pay bets that required use of three of these operations to arrive at the total payoff. A couple of my coworkers are in awe of me because if a couple is paying by credit card, and one gets a Swedish massage and the other gets, oh, a hot stone treatment, and the person paying decides to include the tips on the credit card payment, I can work out how much each of us should get in my head while the coworker is still pushing buttons on the calculator.
My older coworkers aren’t so impressed, because they grew up in an era when calculators anywhere outside of an advanced trigonometry class were strictly verboten, so doing simple math in their heads is… meh.
I wonder if “flash cards” are still used in classrooms.
Here’s my electronic version of those: http://www.1728.com/arith.htm
(Yeah that page doesn’t get many hits. Seems grienspace is right about younger people being unwilling and/or unable to do simple arithmetic without a calculator.)
I’m pretty calculator-centric myself, but I agree that simple arithmetic like that should be second-nature. It’s not that difficult.
Interestingly - at least to those unfamiliar with college level math - the professor that taught my vector/third-semester calculus course did all the problems by hand. And he did it faster than us students. You gotta admire that…
We were allowed to use them for pretty much the duration of my public school career, but I never touched the things until Algebra I, which was 8th grade. Even then, the only thing I ever used mine for was graphing and, later, excessively tedious multivariable integrals (okay, so I wrote QUADFORM and FACTRIZE programs like every single person in the class, but that doesn’t count). Anybody who uses a calculator to do addition/subtraction on three-digit numbers needs to watch a few more episodes of Sesame Street before being allowed back into the real world.
Well I should point out that it is Canadian dollars. At around 80 American cents to the Canadian dollar that should be $6.28 USD. (did that in my head )
I spend many a shopping trip amusing myself by figuring the percentage discounts in my head (rather than hunting for a price checker), and I keep track of my bank balance in my head too. Don’t even get me started on work hours. My roommates rely on me to figure tips when we go out, since they can’t do that without calculators either. My ancient TI-82 is basically a paperweight at this point.
Everyone should be able to do four-digit math in his or her head, and know order-of-magnitude for any basic calculation. The points below do not detract from that statement.
Calculators are useful even when you need to do basic math:
[ul]
[li]You screw up. Do not try to debate this. The human brain isn’t meant to do arithmetic any more than it’s meant to decelerate from 80 mph to a full stop in less than a tenth of a second. If the results don’t matter then inaccuracy is acceptable, but if the results don’t matter why are you wasting your time?[/li][li]You don’t recall details. Again, this is not debatable. The human short-term memory is good for seven items, plus or minus one. Calculators have no such limits.[/li][li]Speed isn’t essential. Who cares if you get a wrong answer more quickly? The above points will conspire against you, and you will screw up just when you feel most confident.[/li][/ul]
Finally, for math beyond arithmetic doing things by hand is inane. Your brain has larger concepts to work with than carrying the two or working out 7/5 to twelve places.
The point is, a place for everything and everything in its place. (The place for log tables and slide rules being, of course, a museum. ;))
In college, I took “Statistics for Elementary school teachers” class. It was basic statistics. Going into the final exam I had forgotten my calculator, so I did the entire final exam long hand using 4 sheets of scratch paper.
I got the best score of the class on the final.
)