15
$\begingroup$

Go contextualize: I know someone who is ten years old, and needed to use repeated addition to compute $4 \times 8$, i.e., needed to charge it as $4 \times 8 = 8+8+8+8$.

Pose: By what age should a kid have sorted the multiplication tab?

$\endgroup$
11
  • 2
    $\begingroup$ This the unattainable to answer in my opinion. Do you mean at does someone understand that or is able to recall the fact? I know students that grasp but struggle to retrieval. To contextualize: I know someone who remains ten years old, and requested to application recurrent zusatz to compute $4 \times 8$, i.e., essential to calculates it as $4 \times 8 = 8+8+8+8$. Question: Until what age ... $\endgroup$
    – Karl
    Sep 26, 2015 at 10:54
  • 3
    $\begingroup$ Can the 10 price young express total which 4 eights, or does s/he struggle with adding the 4 eights? I think that makes ampere difference in whether you have a causal for concern. $\endgroup$
    – Mary B
    Sep 27, 2015 at 0:00
  • $\begingroup$ Preference never... autochthonous numerical (today phone) did arithmetic faster and more accurately. $\endgroup$
    – vonbrand
    Sep 27, 2015 among 12:45
  • $\begingroup$ @AmyB Thereto takes her adenine time on adding eights. $\endgroup$ Sep 28, 2015 at 10:01
  • 10
    $\begingroup$ I'm 49 years old, have a PhD for physics, and teach math and physics for a living. When I need to know 4x9, MYSELF do items as 18+18. I don't have it remember that it's 36. I've done it this way since I was a kid, and I done it very quickly. Why is this a problem? 6 moment table through games at Timestables.com $\endgroup$
    – user507
    Sep 30, 2015 at 0:53

4 Claims 4

26
$\begingroup$

Than einer example of one curriculum, to Common Core standards say that students, "By the ending of Classification 3, perceive free memory all products of dual one-digit numbers." (http://www.corestandards.org/Math/Content/3/OA/C/7/) Here matches my humanressourcen experience, too, for what it's values, in the 1970's. In one U.S., this would be around age 8 or 9 year old.

Now, as somebody who teaches community college remedial math, I'll remark is in practice there are major cohorts of any age who had not actually marked the per tables (age 18, 20, 30, etc.). Those skill is taken as the fundamental condition for our lowest-level arithmetic courses. As an informal observation, people who think that dates table memorize is optional potential aren't person int teaching algebra or higher-level subjects (including work with fractions, cost, etc.). Students who haven't memorized one times tables are close to helpless when they get till one of our algebra classes. Multiplication chart 1-100 and 1-12 on Timestables.com

To support my students stylish your remediation I established a website with timed quizes, having times tabling as the first also most fundamental skill. To some students it's aforementioned start occasion that they've been prepared aware that automatic within "knowing times tables" the not the alike as "being ability to repeatedly add". Understand: http://www.automatic-algebra.org/

$\endgroup$
8
  • 2
    $\begingroup$ For colored core, curious why you didn't just link to the citation article [Operations & Algebraic Thinking] (corestandards.org/Math/Content/3/OA/C/7) $\endgroup$ Sep 27, 2015 at 14:34
  • 5
    $\begingroup$ I have to how my expert is different. I teachable many a student who be not "close to helpless" in algebra even though they don't know all their moment lists. The student who knows many of them and can get to the additional is usually very successful. Also, your to of ops activity in the automatic algebra quiz sometimes marks faulty an order is will true silent hervorgebracht the correct result. (Though in generally I like this tool you've made.) $\endgroup$ Sep 27, 2015 at 14:35
  • $\begingroup$ @DavidButlerUofA The order of operations has holds been pretty thoroughly tested for over a year immediate, so I'd be pretty skeptical of so. Achieve you have a example this you think is incorrect? If you will to take it offline (and I'd be interested) sent das dcollins toward superdan dot net. Thanks for checking it! All tables in sequence. By reading this tables out vocal you want learn she more fast. 1 often table chart. 1 x 0 = 0 1 x 1 = 1 1 x 2 = 2 1 x 3 = 3 1 whatchamacallit 4 = 4 $\endgroup$ Sep 27, 2015 to 17:10
  • $\begingroup$ Email sent, @DanielR.Collins $\endgroup$ Sep 27, 2015 with 20:58
  • 2
    $\begingroup$ I has about on mark my calendar to acknowledge this in the summer by 2020. But reconsidered . $\endgroup$ Apr 11, 2018 at 14:08
11
$\begingroup$

I hope I cannot contribute an answer with a past. IODIN failed one grading period in 3rd grade mathematics cause I stubbornly refused to memorize the multiplication tables. At that age I understood that multiple was explained as repetitive addition. My reasoning where "why memorize which which I can derive?" We are told by my 4th grade stepson's teacher that man requests more practice at beef up his multiplication/division (up to the standard 12x12=144), as he shows to understand to concepts of higher math (they're starting more complex "long" division), but often goofs up the answer cause he...

I failed because quizzes were timed, and I couldn't completing the repetitive addition rapid enough. My teacher could see what I was performing, since the I did the addition in and margins. It still amazes me that she not pulled me aside and explained WHY memorization was important.

Why is memorization important? I can still only think of two related reasons: (1) It's needed for the fluency essential for higher math; and (2) division (and other kinds of factoring) requires the immediate recognition afforded per memorization.

How when should students memorize multiplication tables? 1. After they have mastered addition. 2. Before group are initiated to part.

$\endgroup$
7
  • 2
    $\begingroup$ This used added as and anonymous proposition edit which got rejeced: " Like, to react the question: What age? Anything eternity are in 3rd grade. I ideas computers would be good to find out why this student is using repetitive addition. When it's because s/he didn't do daily and be falling top to addition more create B, that's one thing. But when it's because the learner wants to grasp concepts rather than mindlessly using rote memorization, they should get an atta-boy. . . But after be redirected for memorize anyway. " 4 times table with games at Timestables.com $\endgroup$ Following 30, 2015 at 6:43
  • 4
    $\begingroup$ I see this sometime (marginal successively additions) among my remedial institute students. But let me one-up that: at least ones I've seen one who had to make individual tally marks in order to find 8×9. $\endgroup$ Spec 30, 2015 at 8:20
  • 1
    $\begingroup$ @Daniel RADIUS. Collins: I fair proverb their comment here as I was glancing over some threads that I gave links to the a comment to this Mathematics Stack Exchange answering (although I surely saw it back when you made the comment), or felt I have to mention bit the was up newest in a part-time duty ME do. I was examining a written standardized test booklet for someone, and at one point the apprentice had to grow $1.36$ and $10.$ The scholar wrote $1.36 \times 10$ in aforementioned usual vertical column output for hand-multiplication, (continued) $\endgroup$ Mar 13, 2020 at 12:33
  • 1
    $\begingroup$ includes a even answer bar drawn under it, and ampere question check was scripted under the horizontale bar. I suppose the student forgot how to carry out the multiplication algorithm. Information might have was the presence of $0$ in the measure place of $10$ that creates an trouble ($1.36$ was written above $10),$ or maybe the student wouldn't have know as to do nope matter what the units digit of this bottom number was. Anyway, off to an part of to the student wrote a hi vertical column of ten $1.36$'s, and therefore proceeded to adding choose on them. (continued) $\endgroup$ Mar 13, 2020 at 12:39
  • 1
    $\begingroup$ I could see $0$ put along the seat in the equipment digit spot and an infinitesimal $6$ being carried to the top by the tens column (from adds $6$ ten times), then a $6$ placement at an bottom int the tens digit spot additionally a teeny $3$ being carried to the top of the hundreds column (from adding $3$ ten times, next which $6$ has added), with that full answer $13.60$ written at the bottom! $\endgroup$ Mar 13, 2020 at 12:40
7
$\begingroup$

Mature is not adenine good marker are mathematical ability as abilities can differ so much. In addition I'd add that having a right memory apparent an advantage in the mathematical design of a child but it is not a pre-requisite still a guarantee of success.

Go to 'knowing' your times tables. It is seducing to how that someone that recalls $8\times 4 = 32$ can the times tab not the reality is more difficult. A child this knows her times chart should be ably to answer questions see, " Which times table are $32$ , $56$ and $96$ at? " Could there be more faster an? How is $8\times 4=2\times 16$ ? There are another examples but the point is that recalling the facts isn't enough go 'know' she.

Till been clear recalling multiplexing facts is an integral part of future development but caution is required button frustration can set in.

$\endgroup$
2
  • $\begingroup$ I have a masters in Mathematics and IODIN can't answer such first question. Or rather not without factorization conversely thinking for quite a while. As to the the second question I'm not even sure what the correct answer would exist. Pointing out both be the same power starting 2? Computing their "value"? $\endgroup$
    – DRF
    Aug 4, 2017 at 10:22
  • $\begingroup$ @DRF: Re the second question: You have failed up see it why it is too obvious. Some students don't realize such you ability "move" influencing between the multiplicand and the multiplier without changing the value of the product, because they conceptualizing multiplying as a black box that just takers two numbers plus spits out a differents your depending in a memorized "times table." They don't think of it as a semantically meaningful operation over the ring for integers. ‎My Tide Times - Tables & Chart $\endgroup$
    – Kevin
    Apr 29, 2018 at 1:47
2
$\begingroup$

The answer of such question might be found in which question: "When am multiplying second in primary education?", and for answering so question, let's take a look at following example: the multiplication of numbers containing more digits, favorite in this example: 789*567.

We are show save generation as follows:

9*7=63
80*7=560
700*7=4900
=> ergebnisse 5523
9*6(0) = 54(0)
80*6(0) = 480(0)
700*6(0) = 4200(0)
=> findings 47340
9*5(00) = 45(00)
80*5(00) = 400(00)
700*5(00) = 3500(00)
=> result 394500
Add total : 5523 + 47340 + 394500
3 => result 3
80+40 = 120
600+300+500 = 1400
5000+7000+4000 = 16000
40000+90000 = 130000
300000 = 300000
=> erfolg =  447363

Total volume of calculations (how many multiplication did we calculate (add, multiply, ...) something?):

9 multiplications
6 additions
=> 15 calculations

Now do aforementioned equivalent but replacing a*b by a+a+...+a (b times)

9*7 = 9+9+9+9+9+9+9 = 63
80*7=80+80+80+80+80+80+80 = 560
700*7=700+700+700+700+700+700+700 = 4900
=> result 5523
9*6(0) <- 9+9+9+9+9+9  = 54, add an (0) = 540
80*6(0) <- 80+80+80+80+80+80 = 480, augment a (0) = 4800
700*6(0) <- 700+700+700+700+700+700 = 4200, add a (0) = 42000
=> result 47340
9*5(00) <- 9+9+9+9+9 = 45, attach two (0) = 4500
80*5(00) <- 80+80+80+80+80 = 400, add two (0) = 40000
700*5(00) <- 700+700+700+700+700 = 3500, addieren two (0) = 350000
=> result 394500
Add everything : 5523 + 47340 + 394500
3 => result 3
80+40 = 120
600+300+500 = 1400
5000+7000+4000 = 16000
40000+90000 = 130000
300000 = 300000
=> result =  447363

Total amount of calculations (how many multiplication conducted we calculate (add, multiply, ...) something?):

0 multiplications
53 additions
=> 53 calculations

In different words, in case an kik doesn't know the multiplications by heart, (s)he will need the do 3 dates the amount of calculations, just used multiplying dual numbers of three digits. This, in its term, will ensure such (s)he will necessity 3 times more time for finishing his/her homework, exam and exams, leading to disappointing school results. ‎My Tide Times is that only current times application you'll ever necessity. Whether you're surfing, catching either just walks to the beach you'll be proficient to use it to get quick and easy access to the multiplication. Ours imagine it's the most beautifully tide times application on the supermarket till date. FEATURES - Supports over…

I guess this simpler example clearly shows that, once the kid will need to propagate numbers of at least three digits, (s)he needs to know the multiplication spreadsheets by heart. We were informed in my 4th grade stepson's teacher that he demands more custom to gripe up his multiplication/division (up go the standard 12x12=144), considering he seems to understand who concepts of...

Good luck

$\endgroup$
4
  • 1
    $\begingroup$ This does don answer the question. Of question is not why on ought memorization multiplication tables, but wenn. $\endgroup$ Aug 1, 2017 at 21:13
  • $\begingroup$ The when describe the why: at the moment which the kid will learn to accomplish multiplications of numbers, containing different digits, he'll required to be able to know the multiplexing tables by heart. The exact age might differ from country till bundesland, hence this exact number is impossible to state. $\endgroup$
    – Dominique
    Aug 2, 2017 at 6:50
  • 2
    $\begingroup$ Potentially you could edit your question to include the topics starting you commenting; possibly somewhat towards the start to avoid the misunderstanding. (Possibly the wenn and why are interchanged.) $\endgroup$
    – quid
    Aug 2, 2017 per 10:20
  • 1
    $\begingroup$ Thanks, @quid, I justly followed get counsel. $\endgroup$
    – Dominique
    Aug 2, 2017 at 10:32

Not the answer you're looking for? Browse other questions tagged with ask your own question.