Paul C. Anagnostopoulos
Nap, interrupted.
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Sounds reasonable to me. You do what you gotta do.Conker said:
Calculators: good.
~~ Paul
Do I have a learning disabilty?
- Thread starter Eddie Dane
- Start date
Calculators: good.
~~ Paul
Dancing David
Penultimate Amazing
Speelchuck:good.
jasonpatterson
Philanthropic Misanthrope
I think that this is neither stupid nor illogical, you're simply using the fact that addition is associative to do the problem. That is, (76+20)+3 = 76 + (20+3) I do the same thing all the time when I multiply larger numbers. It's certainly a superior approach to throwing your hands in the air and giving up.
The flip side of this astounds me; that their are 'idiot-savants' with a proclivity for numbers that allows them to calculate six digit factors in a second. I'd love to know what process is taking place in their brains. My father could find whole cube roots of 7 digit numbers in 2 or 3 seconds, but it was a trick, of sorts, easily learned. With these other math savants, it seems to be something utterly different.
Paul C. Anagnostopoulos
Nap, interrupted.
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much thanks; very interesting!
Hi, I'm new here and just came across this posting. I just turned 40 this month and math has given me fits my entire life. I excel at everything else, but math just eludes me. For example, I can add and subtract, and even multiply and divide if given time and I'm not rushed. I can not, however, remember the multiplication table. I have to sit and work out much of it by hand. In high school I never passed a single math course. I have tried much of my life to learn percentages and fractions, and I appear to learn some basics if I'm sitting there working with it, but if I get up and come back to it in an hour, all information I learned is lost.
I was in college in the 90's had to be tutored for remedial math. The head of the tutoring department said that he thought I had dyscalulia and up to that point I had never heard of it. I just thought I was stupid, because that's what I had been told by teachers growing up. I had to take statistics for my major and tried the course 4 times, studied myself to near death, and never passed it.
I'm back in college again and I'm going to encounter some pretty scary math in the next couple of years. I've bought children's math games to help me learn. I seem to 'get it' better through games than just reading it out of a book and trying to understand it. I still maintain hope that this time around I will be able to learn enough to get my degree.
I was in college in the 90's had to be tutored for remedial math. The head of the tutoring department said that he thought I had dyscalulia and up to that point I had never heard of it. I just thought I was stupid, because that's what I had been told by teachers growing up. I had to take statistics for my major and tried the course 4 times, studied myself to near death, and never passed it.
I'm back in college again and I'm going to encounter some pretty scary math in the next couple of years. I've bought children's math games to help me learn. I seem to 'get it' better through games than just reading it out of a book and trying to understand it. I still maintain hope that this time around I will be able to learn enough to get my degree.
Sounds to me like the school started trying to teach you shortcuts before you had a solid grasp of how to do things the "long" way. Also, writing the numbers beside each other (as they are teaching in the schools where I am) doesn't help.
73+26 is easy to type, but has damn all to do with how you work the problem. Write the problem with the numbers above one another like this:
PHP:
73
+26Suffice to say, there are ways of writing the problem that help you follow the correct sequence to do the work and there are ways that obscure what you are actually doing.
Anyway, as others have said, if you have a real problem or suspect you do, then you need to check with a professional.
scissorhands
Banned
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As others have said, there is nothing stupid or illogical about that method, if it works for you, then it works.
I tend to do a workaround in multiplication, due to not memorising all of the times table too well.
Given say a 8*6= ?, something I have a mental block over, then I default to a previously ingrained multiplication of 6, like 6*6= 36 and then add 2*6 to that.
Or I would use the fact that I knew that 10*6= 60, therefore 8*6 is 2*6 less than 60.
9*8=?
Not something I memorised.
Well 10*8= 80 therefore one less 8 is 72.
Convoluted maybe, but it gets there.
scissorhands
Banned
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As others have said, there is nothing stupid or illogical about that method, if it works for you, then it works.
I tend to do a workaround in multiplication, due to not memorising all of the times table too well.
Given say a 8*6= ?, something I have a mental block over, then I default to a previously ingrained multiplication of 6, like 6*6= 36 and then add 2*6 to that.
Or I would use the fact that I knew that 10*6= 60, therefore 8*6 is 2*6 less than 60.
9*8=?
Not something I memorised.
Well 10*8= 80 therefore one less 8 is 72.
Convoluted maybe, but it gets there.
As others have said, there is nothing stupid or illogical about that method, if it works for you, then it works.
I tend to do a workaround in multiplication, due to not memorising all of the times table too well.
Given say a 8*6= ?, something I have a mental block over, then I default to a previously ingrained multiplication of 6, like 6*6= 36 and then add 2*6 to that.
Or I would use the fact that I knew that 10*6= 60, therefore 8*6 is 2*6 less than 60.
9*8=?
Not something I memorised.
Well 10*8= 80 therefore one less 8 is 72.
Convoluted maybe, but it gets there.
There is a video game that I downloaded to help me with the times tables. It's free and it's called Timez Attack. It helped me a lot.
I Ratant
Penultimate Amazing
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A friend says he's got problems with math...
Yesterday he said he will be 53 on Monday.. born in 1952.
I said to him... subract 1952 from 2000, you get 48.
Add 9 (for 2009), you get 57.
A couple guys there agreed that, yes, he's gonna be 53. ???
Yesterday he said he will be 53 on Monday.. born in 1952.
I said to him... subract 1952 from 2000, you get 48.
Add 9 (for 2009), you get 57.
A couple guys there agreed that, yes, he's gonna be 53. ???
Modified
Philosopher
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I'm very good at calculating in my head and that's basically the same way I'd do it, only I'd mentally "transfer" 1 from the 76 to the 23, then proceed. If you're from a country that has coins with a 25 value, dealing with 25s is very natural.
Clownshoes
Scholar
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This is the way I approach simple calculations. I add up the individual digits as if they were stacked on top of one another. I approach problems in my head this way as well. I think visualizing what you are trying to do helps a bunch in simple calculations.
Also as elementary as it sounds I still add digits on my hands. Mostly because I never trusted my mental math with larger numbers (3+ digits) and carrying digits the stacked way. I guess I sort of developed a method to cope with the way I was taught math rather than my own individual logic method..
Its interesting to see how others process information. I think a lot of it has to do with how your taught.
whatthebutlersaw
Dessert Arsonist
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As others have said, there is nothing stupid or illogical about that method, if it works for you, then it works.
I tend to do a workaround in multiplication, due to not memorising all of the times table too well.
Given say a 8*6= ?, something I have a mental block over, then I default to a previously ingrained multiplication of 6, like 6*6= 36 and then add 2*6 to that.
Or I would use the fact that I knew that 10*6= 60, therefore 8*6 is 2*6 less than 60.
9*8=?
Not something I memorised.
Well 10*8= 80 therefore one less 8 is 72.
Convoluted maybe, but it gets there.
I use the same approach, but my brain latched onto other criteria. For multiplying with 9, instead of just learning the table by heart in second grade like the rest of my class did, and which would have been much more practical, I noticed that anything multiplied by 9 could always be added down to make 9. In second grade, I never did this beyond "times 10" as it wasn't required, but as I got older I noticed it actually held:
Simple example: 9*7=63
6+3=9
Bigger example: 9*82=738
7+3+8=18
1+8=9
Bigger yet : 9*2640=23760
2+3+7+6+0=18
1+8=9
and so on. Of course, I have no proof - or any chance of understanding the math required to find a proof - for this, but it worked for everyday purposes and though I grew up to be a math doofus, at least there was this glorious moment in second grade when I actually came up with a simple theorem. The strain must have shut the math part of my brain down forever.
This meant that whenever I came across a small, multiplication (which is the only one you do in second grade) with 9 I would go one down and add up whatever made it nine. I.e for 6*9 my brain would go: one from six is five, five plus what is nine? Four. Five four. Fifty four. 6 times 9 is 54.
Other tricks I utilised to save myself the work of just learning the bally tables was to note that single even numbers multiplied by 6 tended to end in themselves: 6*2=12, 6*4=24, 6*6=36, 6*8=48, so when multiplying odd numbers by six my brain would find the higher nearest even number and then subtract six: 6*7=6*8-6=42.
The only table I couldn't find a trick for was 7 - but since I had tricks for all the other ones, I just did 7s the other way around. (Still talking kiddie school math, you understand, so not many big numbers flying about)
This meant that I calculated instead of rattling off, which actually made me slower than my classmates.
I never ever thought to share this with a math teacher and chose an all humanities package for my upper secondary because my teachers and I agreed that I did not have a math brain, since I was always lagging behind.
The process wasn't speeded up by the fact that I for some reason ascribed the single digits - only the single digits not larger numbers- personalities and disliked some of them causing me to feel some digits fared better to the expense of others, an injustice I was determined to correct. I detested the number 5, which I thought of as a disgusting goody two-shoes, teachers pet and total prigg, and would sometimes change answers if today's assignments had contained - in my opinion - too many fives, in order to let the four come out and play more often. (Four being honest, dependable and a good friend) My teacher at the time found it really weird that I would so often be exactly one off the correct answer. We came to the joint conclusion that I basically sucked at math and left it at that.
With a brain that messed up, no wonder math wasn't for me. I don't think there is a teaching method in the world that could straighten out that mess. (Although I did grow out of the "numbers have personalities" thing. These days, they are just numbers)
I have an unrequited love for math. I love to read about it - especially number theory - but I don't understand any of it. I experience it like I would dadaistic poetry and leave it at that.
Modified
Philosopher
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No? Loosely, and off the top of my head:
For A >= 0,
9 x A = B + 10 x B1 + 100 x B2 ... (where all Bi >= 0)
9 x A = B + 9 X B1 + B1 + 99 x B2 + B2 ...
A = (B1 + 11 x B2 + 111 x B3 ...) + (B + B1 + B2 ...) / 9
So since A is an integer, (B + B1 + B2 ...) must be a multiple of 9.
It is trivial to show that this sum of digits, if not 9 or 0, is less than
A, so if not 9, repeating this process will result in another sum of digits
that is 9, 0, or smaller yet, and so by recursion the recursive sum of
the digits must be 9 or 0. If it is 0, then it can only be that A was 0.
So the recursive sum of digits for A > 0 must be 9.
learner
Graduate Poster
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Your African client sounds exactly like me when I was in business. I was functionally illiterate until my late twenties (47 now and). I used all sorts of tactics to get through difficult situations until one day I got pissed off with the hassle and time wasted. I came clean and was respected for it.
If you are seen to be doing all you can to help yourself you will get nothing but respect.
My target now is to regularly make posts without having to edit for spelling. Ive got a way to go but I will get there.
Good luck
Only two spelling mistakes this time. Not bad. Why two Ls in functionally?
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Interestingly, when I see something like that, my brain automatically does the calculation. My father strongly encouraged me to learn to do calculations in my head. I received a Dataman hand-held toy when I was a kid and loved it. I still have it and hope to give it to my kids. It was basically a bunch of arithmetic games and drills.
I think there's a huge genetic component to this. I feel no shame that I cannot draw freehand worth a crap. Most people who can't don't. But for some reason some people feel ashamed if they struggle with math or spelling. This layman thinks that in many cases it's not a matter of effort but really how you're wired.
My brother and I are very different. I've done lots of programming over the years - it came naturally. I can read books and learn concepts without any trouble. My brother, however, struggled in school. He runs a very successful Mercedes repair shop. He's a great mechanic.
One day I had a printer that was giving me all sorts of fits feeding paper. I called him for an assist. He gave me the line about not understanding computers worth a crap. I told him it was a mechanical issue, and he agreed to look at it for me.
I showed him the printer and described the problem. He popped it open, looked around for a few seconds, flicked a little something with his finger, and closed the case. He fixed in seconds what I struggled with for an hour.
This is a long-winded way of saying I would recommend finding the most expedient ways to get the numbers you need and devote your efforts elsewhere.
Does everyone have learning disabilities?
Compared to whom?
If there exists a measured baseline of what constitutes "Average human ability to learn and understand subject X in time Y" I have yet to hear of it.
We are all better at some stuff and not so good at other stuff.
Sometimes we can use workarounds , sometimes not.
That this is partly a result of experience and partly of neural structure seems fairly clear.
These days it's not considered PC to say someone is a bit dim. We prefer to say said individual has a highly specific learning disability and ascribe it to a neural structure. That way there's no blame for the person himself.
But what is the person himself if not the combination of neural structure and experience?
Eddie- for what it's worth, my arithmetic abilities are much like your own and my conceptual mathematical ability is very weak indeed. I not only think a lot of mathematics is just philosophical bunk, I'm not even convinced that numbers are in a deep sense "real" at all. And I'm totally incapable of explaining what I mean by that.
It's possible I have a rare and profound insight into the Nature of Reality. Or I may be just a bit dim.
I know which I think is more likely.
ETA- And I'm not losing any sleep over it.
Incidentally, I'd add that if a particular neural structure is associated with a "disability"- learning or otherwise- it may also be associated with another advantage, such as emotional stability, better verbal dexterity, ability to visualise more clearly etc- . Brain output is behaviour- and behaviour is so subtle we will be centuries categorising it all and associating it with bits of brain, if that is even possible in theory.
Being unable to count beyond thirty was no disadvantage for 99.999% of human prehistory- and given a calculator, looks to be no major problem in future. If it happens to be associated neurally with (say) the ability to appreciate the loveliness of a flower- how would we ever know?
Compared to whom?
If there exists a measured baseline of what constitutes "Average human ability to learn and understand subject X in time Y" I have yet to hear of it.
We are all better at some stuff and not so good at other stuff.
Sometimes we can use workarounds , sometimes not.
That this is partly a result of experience and partly of neural structure seems fairly clear.
These days it's not considered PC to say someone is a bit dim. We prefer to say said individual has a highly specific learning disability and ascribe it to a neural structure. That way there's no blame for the person himself.
But what is the person himself if not the combination of neural structure and experience?
Eddie- for what it's worth, my arithmetic abilities are much like your own and my conceptual mathematical ability is very weak indeed. I not only think a lot of mathematics is just philosophical bunk, I'm not even convinced that numbers are in a deep sense "real" at all. And I'm totally incapable of explaining what I mean by that.
It's possible I have a rare and profound insight into the Nature of Reality. Or I may be just a bit dim.
I know which I think is more likely.
ETA- And I'm not losing any sleep over it.
Incidentally, I'd add that if a particular neural structure is associated with a "disability"- learning or otherwise- it may also be associated with another advantage, such as emotional stability, better verbal dexterity, ability to visualise more clearly etc- . Brain output is behaviour- and behaviour is so subtle we will be centuries categorising it all and associating it with bits of brain, if that is even possible in theory.
Being unable to count beyond thirty was no disadvantage for 99.999% of human prehistory- and given a calculator, looks to be no major problem in future. If it happens to be associated neurally with (say) the ability to appreciate the loveliness of a flower- how would we ever know?
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Only two spelling mistakes this time. Not bad. Why two Ls in functionally?
Why not? "L" s are nearly as abundant as photons.
Use three if you feel reckless.
