Author Topic: The importance today, of "Times-Tables" ???  (Read 25168 times)

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Offline helius

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Re: The importance today, of "Times-Tables" ???
« Reply #100 on: April 20, 2018, 07:53:14 pm »
I don't think I have ever seen the ÷ sign as part of a pset past Algebra I... certainly not in High School.
 

Offline hendorog

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Re: The importance today, of "Times-Tables" ???
« Reply #101 on: April 20, 2018, 08:09:18 pm »
About a week ago we attended a teacher/parent meeting with our son (last year of primary school).
The teacher suggested we work with him to improve his times tables as it will be required in his intermediate next year.

He has done them in the past as part of homework, along with spelling, but the school hasn't been consistent and so things have slipped a bit. Every year there is a different approach. This lack of consistency seems to be one of the issues with early schooling, at least in this country.

The other issue in the teacher meetings, is that the teachers seem to be stuck in transmit mode.
 

Offline rstofer

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Re: The importance today, of "Times-Tables" ???
« Reply #102 on: April 21, 2018, 03:20:32 am »
In any professional publication one or other of the above forms would be expected and preferred.

If it was really wanted on a single line one would probably write something like this: \$(6 / 2)(1+2)\$

I was thinking about Fortran.  Or any other language that has operator precedence.  Yes, there is a missing '*' before the '(' but still, the result will be 9.  I'm using this as an object lesson for my grandson in the use of parenthesis to force the order of evaluation.
 

Offline AG6QR

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Re: The importance today, of "Times-Tables" ???
« Reply #103 on: April 21, 2018, 05:27:10 am »
My kids are in elementary school, and have been learning their multiplication tables.  I told them to do it the way I did:

To multiply by two, just double the number.

To multiply by three, double it and add another copy of it.

To multiply by four, double it and double the result.

To multiply by five, halve it and move the decimal one place to the right.

To multiply by six, double it and triple it.

To multiply by seven...  Sevens are hard.  We'll come back to them.

To multiply by eight, double it, double the result, and double that.

To multiply by nine, subtract one from the number to get the tens digit, then for the ones digit, choose the number that, when added to the tens digit, sums to nine.

To multiply by ten, move the decimal point.

You don't need the 11s and 12s any more than you need the 13s, 14s, 15s, etc.  You can get them via the normal methods for two-digit multiplication.

Now, back to the sevens.  To multiply seven by any other number, use the rule for the other number.  That still leaves seven times seven.  You have to remember that it's 49.

Out of 100 multiplication facts, there's only one you've got to memorize.  7x7=49.  Surely you can memorize that one.


Naturally, with practice, you'll start to memorize some of the other multiplication facts, and get faster at them.   But you can also get pretty fast at doubling with practice.  Does it really matter whether you memorize them or figure them out on the fly?
 

Offline Brumby

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Re: The importance today, of "Times-Tables" ???
« Reply #104 on: April 21, 2018, 05:48:27 am »
Normally I would not engage in this sort of thing [edit] too deeply [/edit], but the accusations are pretty intense and have been made public.  So here it goes...

I do apologise in advance to the rest of the membership and promise to not engage in a lengthy debate.

'Brumby' seems to prefer 'Yep..', 'Nope..', {quote} then 'yep..' without 'adding' to
anything at all except his unadulterated 'Piousness'.... He seems to now 'seek' out
my many/varied Posts now,
Really?  I tried to avoid posting in any of "your" threads because of the risk of this sort of reaction, but I thought I would add my own two cents' worth in the hope that things had settled.  This was done with no sense or intention of malice, yet it seems simply posting in one of "your" threads is malice enough.
Quote
(even though I have moved on...),
Clearly you haven't.  The previous fracas was over 2 months ago.

Quote
from a time that he
chose to (attempt to) 'Belittle' me repeatedly.... when I 'dared' to ask for a resolution
on this 'Forums' MAIN? forum topic.
See below.
Quote
This 'Demi-God' (in his Godness & Greatness)
decided at 2am one morning,
See below.
Quote
(with nothing else to do obviously),
See below.
Quote
to RANT at me,
See below.
Quote
and
tell me I am just a "TROLL"...
See below.  Read what I wrote.
Quote
(Haah?! it was MY post he was continuously abusing??).
After swallowing my pride/rights, I apologized to him, and explained all that I could.....
'HE' then ridiculed me about what I offered, and repeated how 'I'm' just a "TROLL" ????
Well I have many scientific interests, that go WAY beyond listening to this "No-Life",
and as such I keep posting/discussing in areas "I Hope" is beyond 'his' REALM.....
I'm a peaceful Pensioner, who likes to invoke dialog with REAL people, not Demi-Gods...
Like you said:
Wow, what an interesting Saga that all was... (again  :) )

I'm sorry that you feel the need to tear me down, but it is clear you need to.  I don't believe I have said anything is this thread to warrant such a tirade, but it seems rather obvious you were looking for an excuse to resurrect ill feeling from a previous exchange.

To those wondering - yes, there was an apology (totally unsolicited and completely unexpected), but it was a PM to me.  I would have thought a post to the forum would have been more appropriate.  What hasn't been stated is that my reply was sent 62 minutes later.  Since that PM was private communication sent to me, it would be inappropriate for me to disclose it - but I am happy to present my response - the "RANT" - for others to judge.  Here is the complete, unedited message:

I can understand your embarrassment - but when people were telling you to "walk away", they were actually giving you the best advice to minimise that embarrassment.  You chose to ignore that and demand it gets resolved the way you wanted - which only made it worse.  In the end, you were still pig-headedly pressing for your solution.  Sorry - but that is arrogant and typical of trolls.

Now that the thread has been locked, it will fade and most people will not think about it again - but it will be there as a permanent record.

We tried to tell you the best way ... but noooooo!  You had to keep pushing.


Please note that this response is not an invitation to engage in further discussion on the matter.  It has been given as an acknowledgement of your reaching out and to encapsulate key points.  I hope there will never be a need to speak of these again.

I have been an active member on this forum for a number of years now - and I leave it to other members to judge me on my actions.
« Last Edit: April 21, 2018, 07:26:06 am by Brumby »
 

Offline John Coloccia

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Re: The importance today, of "Times-Tables" ???
« Reply #105 on: April 22, 2018, 06:11:09 pm »
My kids are in elementary school, and have been learning their multiplication tables.  I told them to do it the way I did:

To multiply by two, just double the number.

To multiply by three, double it and add another copy of it.

To multiply by four, double it and double the result.

To multiply by five, halve it and move the decimal one place to the right.

To multiply by six, double it and triple it.

To multiply by seven...  Sevens are hard.  We'll come back to them.

To multiply by eight, double it, double the result, and double that.

To multiply by nine, subtract one from the number to get the tens digit, then for the ones digit, choose the number that, when added to the tens digit, sums to nine.

To multiply by ten, move the decimal point.

You don't need the 11s and 12s any more than you need the 13s, 14s, 15s, etc.  You can get them via the normal methods for two-digit multiplication.

Now, back to the sevens.  To multiply seven by any other number, use the rule for the other number.  That still leaves seven times seven.  You have to remember that it's 49.

Out of 100 multiplication facts, there's only one you've got to memorize.  7x7=49.  Surely you can memorize that one.


Naturally, with practice, you'll start to memorize some of the other multiplication facts, and get faster at them.   But you can also get pretty fast at doubling with practice.  Does it really matter whether you memorize them or figure them out on the fly?

I think about it a different way, but this is generally how I do math too. Memorization is nice so you can recall basic things instantly, but it's useful to have a "feel" for numbers as well. At least it is if you use them frequently for work. Because what do you do when 5*33 comes up? Something like that came up a week or two ago, and I blurted out "that's 165." They're like, "why do you know that off the top of your head?" or something to that effect.  I explained, "well, that's just 33/2 * 10...30/2 is 15, and another 1.5 gives me my three, so it's 16.5 * 10." And of course, I look like a weirdo, but it's actually pretty easy to do. Most numbers are close to other numbers that are easy to deal with, and then it's just a matter of fixing it up a bit.

Very useful for someone like me that has an absolutely atrocious memory. If I actually had to memorize multiplication tables and things like that, I'd be toast. I think stuff like this is what they're trying to do with our new math curriculum in the US, but the way it's implemented is horrible. We've traded one blind procedure for another without giving any real understanding.

If it were me, I wouldn't even teach long division and multiplication. It's not a useful skill for most people, IMHO. That's what calculators are for. I would only teach techniques that allow you to calculate reasonably sized values in your head, and arithmetic tests would be SHOW NO WORK...points off if you write anything but the answer.
 

Offline Distelzombie

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Re: The importance today, of "Times-Tables" ???
« Reply #106 on: April 22, 2018, 08:04:36 pm »
As someone on the first page already said: Learning by tables is inherently flawed. It can easily be seen/understood what we mean by using this analogy I came up just now:
A metalworker learns some basic things about temperatures and metals. He knows at a certain point the metals starts to glow. He uses a device that measures color and brightness and gives him a number. He memorized a table that gives him the temperature in degrees Celsius. that corresponds to the number. (It's hypothetical.)
0 = 0°
0.5 = 150°
1 = 300°
2 = 400°
3 = 500°
...
7 = 900°
...
13 = 1500°

One day he wonders what would happen if he heats the metal further and further. (This doesn't have to be absolutely realistic, I warn ya) So he builds a heater, leaves the room and observes the reading on the device while cranking up the heat. The reading and thus the reading rises up to 13. (That is unfortunately the maximum the device can read... Hehe "unfortunately"! See what I did here? [It's lame.]) He awaits any further changes and keeps heating.
At some point the device starts reading lower numbers again. (It's a VERY robust device) He has no reason to distrust the device and assumes his heater broke (I'd actually hope so, but nvmd) and that it really is starting to cool down. He waits for the reading to reach zero and then moves to disassemble the device - and immediately went up in plasma vapors once he came anywhere near it.
Huh? What was his mistake?  ???

Well, first: He forgot to turn off the heater, and second: He didn't know how the underlying mechanics of particle excitation change the wavelength of the energy emission of the heated material, and how limited his devices response to certain frequency ranges is. The device was made to aid in quick temperature assessment in the range of 700 to 450nm energy emissions. He didn't knew that the device couldn't register high energy gamma rays and would show zero instead of billions.

You see, being forced to memorize the contents of a table instead of learning how to create said contents from nothing, can kill you.

Even if you just provide a table for error-checking purposes you are making a fool out of people: If they don't learn how to properly troubleshoot the mistakes they made they are not having a good understanding of the whole thing in the first place.
Just look at the state of Logic in everyday life. It's almost gone entirely!
« Last Edit: April 22, 2018, 08:14:25 pm by Distelzombie »
 

Offline GlennSpriggTopic starter

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Re: The importance today, of "Times-Tables" ???
« Reply #107 on: April 24, 2018, 02:07:46 pm »
Well if you want a peaceful life, why make a post that dredges up some spat you've had elsewhere with Brumby in an unrelated topic? That does seem to be trolling for a response. 

Oh and please, less smilies, less brackets, less ... ellipses, less random punctuation in general and RANDOM changing into ALL CAPS in the middle of run on sentences. It makes it incredibly hard to read what you've written.

Dear 'Cerebus'.....  I was not aware that Mathematics was a favorite topic of 'Aardvarks', or why you read this far?
'HE' was mentioned, because he usually makes some Pious remarks when I post something, & here was no exception !
I have ZERO interest in 'your' thoughts beyond that, so please stick to 'licking ants' mate......

OH... and as for your...... "and please, less smilies, less brackets, less ... ellipses, less random punctuation " diatribe,
do you now feel like a 'bigger' 'man' in your personal attack, beyond your apparent need to lick 'someone's' butt (???).
Well, every 'punctuation' mark I use is for a reason, as raw text says/highlights/means nothing..........

Ignoring YOU (from now on), will be easy.....   Back to the REAL commenters that the rest of us love here.....
Diagonal of 1x1 square = Root-2. Ok.
Diagonal of 1x1x1 cube = Root-3 !!!  Beautiful !!
 

Offline GlennSpriggTopic starter

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Re: The importance today, of "Times-Tables" ???
« Reply #108 on: April 24, 2018, 02:24:18 pm »
Oh.. shit... I almost forgot 'Brumby' !!!!!!!
I know you can't help it mate....  "Gods" can't !!!!!!!!!
(Maybe spend less time trying to defend yourself at 2 or 3 Am with nothing else to do......)

Anyway, I sincerely thank the 'general' (mere) population who engaged in this meaningful
dialog, in a meaningful & productive way, and truly enlightened me. Thank you !
Glenn Sprigg.  (No name ever hidden  :) )
Diagonal of 1x1 square = Root-2. Ok.
Diagonal of 1x1x1 cube = Root-3 !!!  Beautiful !!
 

Offline Cerebus

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Re: The importance today, of "Times-Tables" ???
« Reply #109 on: April 24, 2018, 02:29:10 pm »
Well if you want a peaceful life, why make a post that dredges up some spat you've had elsewhere with Brumby in an unrelated topic? That does seem to be trolling for a response. 

Oh and please, less smilies, less brackets, less ... ellipses, less random punctuation in general and RANDOM changing into ALL CAPS in the middle of run on sentences. It makes it incredibly hard to read what you've written.

Dear 'Cerebus'.....  I was not aware that Mathematics was a favorite topic of 'Aardvarks', or why you read this far?
'HE' was mentioned, because he usually makes some Pious remarks when I post something, & here was no exception !
I have ZERO interest in 'your' thoughts beyond that, so please stick to 'licking ants' mate......

OH... and as for your...... "and please, less smilies, less brackets, less ... ellipses, less random punctuation " diatribe,
do you now feel like a 'bigger' 'man' in your personal attack, beyond your apparent need to lick 'someone's' butt (???).
Well, every 'punctuation' mark I use is for a reason, as raw text says/highlights/means nothing..........

Ignoring YOU (from now on), will be easy.....   Back to the REAL commenters that the rest of us love here.....

You've got troll written all over you mate, otherwise why would you turn a polite request to adopt a more readable writing style into a "personal attack" and spend so much time crafting such a personalised reply. Well, perhaps crafting is too  skilled a word for it, but it's clear the intent was to try and get some intemperate response out of me. As to ignoring me, good, but I bet you don't have the self control to let me have the last word.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline Brumby

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Re: The importance today, of "Times-Tables" ???
« Reply #110 on: April 25, 2018, 05:51:19 am »
Wow, what an interesting Saga that all was... (again  :) )
(I'm the original 'poster' again...)
My hat's off to the gentleman from the U.S. (and others...), that stated that their kids
ARE taught the times-tables, and that it is a 'requirement'...  That's GOOD !!  :)
But it still sadly doesn't 'here'. (In Australia. No Aussie jokes please  :D)......
I can/have asked my 1st year high-school grand-kids, and their friends, the likes of....
"What is 6x6", or "what is 8x4".... let alone.... "what is 9x7"... (F%$# that's hard!),
and NONE of them can tell me !!!  They ALL have iPhone/Android 'Tablets' these days
in class, (so no need for ancient 'Calculators' ), [lets show them a slide-rule haha].

What is it about a lot of you responders, that make you think that any/all of your own
'methods', and the 'Effort' it takes to remember it/them, is ANY better than SIMPLY
remembering BASIC times-tables, from/with which anyone can calculate anything ??
I RESPECT all your 'abilities'..... but what are you fighting against ??? Seriously ??
May we all, (teachers, parents, grandparents) simply teach our kids the 'basics'  :)

'Brumby' seems to prefer 'Yep..', 'Nope..', {quote} then 'yep..' without 'adding' to
anything at all except his unadulterated 'Piousness'.... He seems to now 'seek' out
my many/varied Posts now, (even though I have moved on...), from a time that he
chose to (attempt to) 'Belittle' me repeatedly.... when I 'dared' to ask for a resolution
on this 'Forums' MAIN? forum topic.  This 'Demi-God' (in his Godness & Greatness)
decided at 2am one morning, (with nothing else to do obviously), to RANT at me, and
tell me I am just a "TROLL"... (Haah?! it was MY post he was continuously abusing??).
After swallowing my pride/rights, I apologized to him, and explained all that I could.....
'HE' then ridiculed me about what I offered, and repeated how 'I'm' just a "TROLL" ????
Well I have many scientific interests, that go WAY beyond listening to this "No-Life",
and as such I keep posting/discussing in areas "I Hope" is beyond 'his' REALM.....
I'm a peaceful Pensioner, who likes to invoke dialog with REAL people, not Demi-Gods...


Well if you want a peaceful life, why make a post that dredges up some spat you've had elsewhere with Brumby in an unrelated topic? That does seem to be trolling for a response. 

Oh and please, less smilies, less brackets, less ... ellipses, less random punctuation in general and RANDOM changing into ALL CAPS in the middle of run on sentences. It makes it incredibly hard to read what you've written.

Dear 'Cerebus'.....  I was not aware that Mathematics was a favorite topic of 'Aardvarks', or why you read this far?
'HE' was mentioned, because he usually makes some Pious remarks when I post something, & here was no exception !
I have ZERO interest in 'your' thoughts beyond that, so please stick to 'licking ants' mate......

OH... and as for your...... "and please, less smilies, less brackets, less ... ellipses, less random punctuation " diatribe,
do you now feel like a 'bigger' 'man' in your personal attack, beyond your apparent need to lick 'someone's' butt (???).
Well, every 'punctuation' mark I use is for a reason, as raw text says/highlights/means nothing..........

Ignoring YOU (from now on), will be easy.....   Back to the REAL commenters that the rest of us love here.....


Oh.. shit... I almost forgot 'Brumby' !!!!!!!
I know you can't help it mate....  "Gods" can't !!!!!!!!!
(Maybe spend less time trying to defend yourself at 2 or 3 Am with nothing else to do......)

Anyway, I sincerely thank the 'general' (mere) population who engaged in this meaningful
dialog, in a meaningful & productive way, and truly enlightened me. Thank you !
Glenn Sprigg.  (No name ever hidden  :) )
 

Offline Distelzombie

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Re: The importance today, of "Times-Tables" ???
« Reply #111 on: April 25, 2018, 06:34:30 am »
Nice archiving, Brumby. ???

Anyway. GlennSprigg it took me a while to write and imagine my post on the last page. Could at least say something?

Offline Brumby

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Re: The importance today, of "Times-Tables" ???
« Reply #112 on: April 25, 2018, 08:02:22 am »
Nice archiving, Brumby. ???

After the last effort, it seemed judicious.
 

Offline IanMacdonald

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Re: The importance today, of "Times-Tables" ???
« Reply #113 on: April 25, 2018, 08:04:12 pm »
Far too much educational time is spent on hifalutin' maths like integral calculus or imaginary numbers, and far too little on the skills which are needed by most people.

Mind you, same is true in other subjects. For example the manic obsession with using OOP coding for even the tiniest program in comp sci courses, whilst the same students have no idea how to avoid typical IT security gotchas. 

Education is like a building; if the foundations are no good, the rest will eventually fall over. The more top-heavy you make it, the sooner that will happen.

Make a good foundation, and people will add more structures to it over time, as required.
 

Offline Distelzombie

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Re: The importance today, of "Times-Tables" ???
« Reply #114 on: April 26, 2018, 01:44:46 am »
Exactly. I always wondered why there are no Philosophy classes in normal elementary and upwards schools. (Germany)

Offline rstofer

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Re: The importance today, of "Times-Tables" ???
« Reply #115 on: April 26, 2018, 02:51:51 am »
Far too much educational time is spent on hifalutin' maths like integral calculus or imaginary numbers, and far too little on the skills which are needed by most people.

A lot of us are engineers by education and we hope our offspring take a similar path.  That path WILL require imaginary numbers (particularly for EEs using Euler's identity) and it will require all 4 semesters of calculus (up through differential equations).  Of course, we are not 'most people'.  We can do hard math...

Trade education is available at most community colleges and, just guessing, ALL junior colleges in California.  That's good!  We need trained techs!  There's room for both types, engineers and techs.
 

Offline rstofer

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Re: The importance today, of "Times-Tables" ???
« Reply #116 on: April 26, 2018, 02:55:46 am »
Exactly. I always wondered why there are no Philosophy classes in normal elementary and upwards schools. (Germany)

It is a required course at our local junior college or as a lower division requirement of Cal State colleges and universities.  There may be a way to avoid it by substituting another general education class but I don't think so.
 

Offline Distelzombie

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Re: The importance today, of "Times-Tables" ???
« Reply #117 on: April 26, 2018, 03:05:19 am »
Exactly. I always wondered why there are no Philosophy classes in normal elementary and upwards schools. (Germany)

It is a required course at our local junior college or as a lower division requirement of Cal State colleges and universities.  There may be a way to avoid it by substituting another general education class but I don't think so.
It should start in elementary school, or at least in middle school. Definitely. I mean you learn basic Logic, Ethics ... stuff! Very important.




Edit: I think nobody is taking my post back then seriously: https://www.eevblog.com/forum/chat/the-importance-today-of-_times-tables_/msg1488705/#msg1488705
So here is one more knowledgable person with the same opinion, in paper form. I can produce more if needed: https://bhi61nm2cr3mkdgk1dtaov18-wpengine.netdna-ssl.com/wp-content/uploads/2017/03/FluencyWithoutFear-2015-1.pdf
« Last Edit: April 26, 2018, 03:37:57 am by Distelzombie »
 

Offline GlennSpriggTopic starter

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Re: The importance today, of "Times-Tables" ???
« Reply #118 on: April 27, 2018, 01:31:52 pm »
Nice archiving, Brumby. ???
Anyway. GlennSprigg it took me a while to write and imagine my post on the last page. Could at least say something?

Dear Distelzombe you are SO right and deserve a reply !!!
(I apologize for being distracted by that "war of words"  :) )
I read your reply twice, and it is interesting to say the least. I'm pretty sure I get what you are saying mate,
with your analogy, however I don't think it relates to the point that I was trying to push forward......
I understand limits of 'scale' within known 'norms' and outside of those 'norms. (I was also an electronic
Instrument Technician). I can appreciate under/over off-scale readings in ways that you might not think
I can.  (The technical term is 'burnout'). GIVEN, that if a relative reading went seemingly ridiculously high
etc, (as in your 'norm' from 0-7 now being say '18'... (would not be registered as such though), then we
would need to rethink all the parameters. However my friend, this does not change the basic maths I pose??

We are not talking about running out of 'Basic' numbers..... (digits 0-9), but the NEED to know the BASICS
off by heart, like 6x6, or 5x5, or 8x8.... (Ok... the 'typical' kids poster goes up to 12x12 !).
When a question/problem/step is say.....  7x7 you NEED to know that the answer is '49' (What is simpler?)

I'm left wondering what people have against 'knowing' except that they don't know/remember !!!!
Why do people fight it ??  Just re-learn, and pass it on to kids/grandkids if 'teachers/parents' won't/can't ??
Simple example....      23 x 54... Not initially KNOWN, but easily calculated...
    23
 x 54
-----
'ASSUMING' the 1st step is 4 x 3, (= 12), HOW ARE YOU GOING TO KNOW THAT !!  if not by logic/heart.
Do you see what I mean ?? There are no SUB steps to 'calculate' that, unless counting 'beans' etc ??
People have quoted other ways to say "Simplify Fractions" etc etc but that's not relevant... xx

FORGET all the dialog in this post, from the original question/statement through to HERE......
I'm now re-asking/stating a simple maths question, (no 2 digit numbers in the question)......
What is    6x9    !!!!!!!   What is WRONG with simply KNOWING that it is  '54' ?? in the middle of a
complex multi-stage calculation you are working on?   Someone else here might say......
"Oh.... well that's the same as 6x10 = 60, -6 = 54..."  (at every step in your 'sumation'?)....
Maybe I would be 'knit-picking' if I then said/asked... "how do you know automatically  that 6x10 = 60"...
(well, that's obvious ??).....   no it is not to the uneducated.  So is '8x8' or '6x6'..........

What 'confuses' me, is why people 'fight' it ??   Just 'RE'-Learn it !!!    :)
Diagonal of 1x1 square = Root-2. Ok.
Diagonal of 1x1x1 cube = Root-3 !!!  Beautiful !!
 

Offline Distelzombie

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Re: The importance today, of "Times-Tables" ???
« Reply #119 on: April 27, 2018, 06:56:10 pm »
Your point was, or is, that you explain "students being unable to calculate equations" with "they are not learning tables anymore", right?
May point with that post was to show you (and others) how problematic it can be when you never learn why 6x6 equals 6. ("It's devils work!" ... No it's logic.)
I wonder why didn't saw the real problem with your "niece"s abilities, when you finally asked her what 30*40 is. (Why quotation marks, btw?) It' is obviously the she lacks the "number-sense". Since someone explained they ARE learning tables in early school, you should see the answer already.
You also lack the number-sense, don't you? (Judging by your questions.) You probably never learned to aquire a sort of number-sense.
As I've shared in the post before, learning by tables doesn't give you a very good number-sense. (The bottom link)


I don't know if I have a good number-sense or not, but I would go at the problem like this:
23*54 // 20*50 + 20*4 + 3*50 + 3*4 // 10*50*2=1000 + 2*4*10=80 + 3*50=150 + 3*4=12 // 1000+150+12=1162 + 80= 1242 (I am a slow calculator)
That's the simplest way I could find while I was writing it down here. I would probably use a slightly different route if I had less time to think about the route. (Especially at the end where I was switching the interim results around) And I haven't learned that. That's just done a priori.


"HOW ARE YOU GOING TO KNOW THAT" 3*4 equals 12? I go the easy route on such small number if I can not remember the result right of the bat: 4+4+4. May sometimes be faster as trying to remember the result.


"We are not talking about running out of 'Basic' numbers..... (digits 0-9), but the NEED to know the BASICS
off by heart, like 6x6, or 5x5, or 8x8.... (Ok... the 'typical' kids poster goes up to 12x12 !).
When a question/problem/step is say.....  7x7 you NEED to know that the answer is '49' (What is simpler?)"

Running out, huh? You say poster, does that mean it is readily available at a moments notice? That is very bad if you actually want to learn something real. You're just learning how to look up a result in a table if you're not careful. Anyway:
That is simple, yes. But it also MAKES YOU simple.


"What is    6x9    !!!!!!!   What is WRONG with simply KNOWING that it is  '54' ?? in the middle of a
complex multi-stage calculation you are working on?   Someone else here might say......
"Oh.... well that's the same as 6x10 = 60, -6 = 54..."  (at every step in your 'sumation'?)....
Maybe I would be 'knit-picking' if I then said/asked... "how do you know automatically  that 6x10 = 60"...
(well, that's obvious ??).....   no it is not to the uneducated.  So is '8x8' or '6x6'.........."

Nothing is wrong with knowing the result, if you got to it yourself beforehand. And isn't "60-4" just as fast as remembering the result anyway?
How do you know automatically that 6x10 = 60? That's not nitpicking, that is: Not understanding the basics of Mathematics. OFCOURSE it is not obvious to the uneducated. What is your point?


People fight it because it is frustrating, excruciatingly boring and it goes against current educational-psychology and make students cry. (proof available, see link) I just got a good feeling from finding the right solution to this mathematical problem. Like the feeling you get when you finish something you were building. You don't get that when you learn tables!


Kind regards :)

Online Bud

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Re: The importance today, of "Times-Tables" ???
« Reply #120 on: April 27, 2018, 07:56:43 pm »
Bullshit. I did not cry when i learned it and it helped me all my life.
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Offline DimitriP

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Re: The importance today, of "Times-Tables" ???
« Reply #121 on: April 27, 2018, 11:53:49 pm »
Quote
People fight it because it is frustrating, excruciatingly boring and it goes against current educational-psychology and make students cry.

Yeah..so is writing, saying please and thank you, dotting "I"s and crossing "t"s, washing  hands after using the restroom, tying your shoelaces, filling up the car with gas, replacing the empty roll of toilet paper,  calling mom and dad on their birthdays and anniversary, putting on clean socks and underwear after taking a shower.
And lest add "doing laundry" to the list of frustrating and excruciatingly boring tasks that we routinely perfom daily.

As for the "current" educational psychology...well...since it's "current"..we should give it a few years until it changes.
We are not talking about learning to fly a plane by memorizing which buttons and levers to push pull of flip.
And we are not even talking about "learning by tables".

We are talking about "The Times Tables"
We are talking about hearing "8x8" and the next thing that pops into your head is "64".

Like being in a swimming pool playing Marco..........Jonathan - Ha! just kidding ...Polo!     ( I don't know the geographic distribution of this game - so this might not mean much to many)

I don't know how one cannot "know " WHY eight times eight is sixty four.
If you take eight bags of marbles with eight marbles in each and you count them all, ( that can be boring the second time you do it ) .....and provided you can count up to 64 !!! , you'll "know" why 6x6 is 64.  ( of course counting ...is yet just another table, just like knowing the days of the week, and the names of each month...tables...funny how that works)

I'll stop here before a let everyone know how I really feel .

I guess Bud put it best
Quote
Bullshit. I did not cry when i learned it and it helped me all my life.



   If three 100  Ohm resistors are connected in parallel, and in series with a 200 Ohm resistor, how many resistors do you have? 
 
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Offline Distelzombie

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Re: The importance today, of "Times-Tables" ???
« Reply #122 on: April 28, 2018, 01:11:43 am »
Did does nobody get it?
I was criticizing tables because you can't as easily calculate what's beyond those tables as someone who learned math differently.
Am I so unprecise?

Offline Cerebus

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Re: The importance today, of "Times-Tables" ???
« Reply #123 on: April 28, 2018, 02:07:13 am »
Did does nobody get it?
I was criticizing tables because you can't as easily calculate what's beyond those tables as someone who learned math differently.
Am I so unprecise?

No, I get your point, I just don't see much mileage in any continued debate. I doubt there's much chance of you changing the minds of the "It was good enough for me" school of thought. When you have participants who bewail that children nowadays do not learn times tables in the way they were taught in maths classes, but eschew all that they were taught in English classes I suspect you're on a hiding to nothing.
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Offline IanB

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Re: The importance today, of "Times-Tables" ???
« Reply #124 on: April 28, 2018, 02:17:03 am »
Did does nobody get it?
I was criticizing tables because you can't as easily calculate what's beyond those tables as someone who learned math differently.
Am I so unprecise?

If we know the tables we can more easily calculate what is beyond the tables. That is the whole point of the tables, they are building blocks.

For example, if I want to know what is 16 x 14, I can quickly see it is the same as 4 x 8 x 7, and I know right away that 8 x 7 = 56. So now 4 x 56 is easy, it is 224 (again, because I know right away that 4 x 50 = 200 and 4 x 6 = 24).

So, we don't agree with you. It is not a case of learning one thing or another, it is a case of learning all the things, and learning many different ways. The more you learn, the more you can do.

 


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