Master your Times Tables (10-20x) in 5 minutes - Easy Math Trick!

This is the easiest way to learn your times tables from 10 to 20 is to use this shortcut.
What's more there is an easy visual explanation WHY this works!
On beyond Zebra!
To donate to the tecmath channel:paypal.me/tecmath
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[@MacheteBushcraftAustralia]

Another dad & son team that has been following your channel for a long time now. You have been a huge help over the past few years. I'm slowly relearning everything I forgot so I can share it with my young one. Keep up the great work mate. You are making a big difference!

[@tecmath]

Thank you both! Great to hear you learning together.

[@4damski]

@@tecmath same here...

[@ursulagreen8374]

I'm not great a math, and my daughter's even worse. I'm homeschooling so this is helping me help her.

[@tecmath]

Thanks Ursala. How's homeschool going?

[@ursulagreen8374]

@@tecmath well this is the easiest year so far. My daughter is finally in a place she can work on her own without me right there. I actually have some free time. She has a hard time with math, so the past few years I took her off her grade level, and started from the beginning, more complex than 1+2, and I can stay on the problems till she gets it, and can do it on her own without help. I make her work the problems. Luckily I can print out worksheets to help me so I don't have to create my own. Theres many resources online. Glad I found you, because I also have a short memory, and can't remember from one year to the next and have to refresh with videos. Thanks for your help,, making it easier.

[@tecmath]

@@ursulagreen8374 that sounds good. I teach in a school, but a few years back I took my kids out for a year whilst we travelled around Australia (sounds glamorous... we lived in a tent!). I found with 30 - 40 minutes a day of teaching the kids where they were at that they ended up well ahead of their classmates when we got back.

[@lachlanmtb7540]

You just insulted you child so hard

[@ursulagreen8374]

@@lachlanmtb7540 no, the reality of children and understanding math is not insulting. I'm out here finding resources to help her. Your being childish. Thisnis not high-school. Or worse, middle school.

[@mariorodriguez1148]

I’m a math teacher. I love it! A different way to look at the distributive property. Your first method is how we teach multiplication of polynomials. Well, the part where you grid it out. I’ll have to noodle with it and see how to apply it to numbers >19

[@nigelmitchell5618]

I would like to thank you. I have never been good at maths, therefore I never passed my GCSE maths. I had to do this paper for a management course my company wanted me to do. I am not a young man, therefore struggle to retain info. I found your you tube channel, your explanations and tips and tricks are fantastic. I passed my managers course, but what I was most proud of I passed my GCSE maths paper. This was down to your easy to understand instructions, and the way you look at maths problems. Cheers for the help, the time and effort you put into your channel.

[@FernandoLopez-wk3dh]

Don't mind those people who criticize. You had explained well enough in your past videos why it works. They just haven't seen them and given comments without really watching or understanding. I learned so much from your videos, so thank you.

[@tecmath]

I'd accepted it as a fair criticism... and liked the graphical explanation. Thanks for your comment.

[@dawnbreakerii204]

Personally, love the voice, quite expressive, and I, personally, clearly understand you. You have taught me quite a bit about math shortcuts. God-speed, tecmath

[@tecmath]

Thanks

[@katc6128]

I only just stumbled across your channel for the first time tonight (popped up in my recommends). Just wanted to stop and say how delightful your videos are, I've already binged quite a few. I enjoyed the visual for the explanation, it really made the workings of the trick 'click'. Thanks for the cool math content, you have a new subscriber!

[@cvdinjapan7935]

I don't think asking why a shortcut works is a complaint about your videos, exactly. I think it shows the person is fascinated by the process and wants to know why it works. If anything, that's a compliment.

[@HellHappens]

I love your channel! I'm in Algebra and I'm finally understanding it. I couldn't grasp it in Highschool and now I'm actually beginning to enjoy mathematics. I don't think I want to go super high into it but I like knowing that it's possible for me to learn.

[@darkzak47]

Your voice is fine. In fact it’s relaxing, non-threatening and quite distinctive. Not much you can do about people’s negative comments

[@Metal-Josh]

Ive always liked the tricks, but I do like the explaining how it works. I can sometimes understand why it works, but it good to see why in case a person to know or needs to know to better understand

[@tecmath]

I read a few of those comments and thought it was a valid criticism. Thanks for your comment.

[@x-tremespeed]

The way I like to do anything *9 is to *10 then subtract *1 (14*9 becomes 14*10=140 then 140-14=126). Both ways are good, this way is just a bit easier in my head 🙂

[@chocolateangel8743]

I do 14 X 9 like this: 9(10 + 4) = 90 + 36 = (100 + 36) - 10. If I were gonna subtract 14 in my head, I would think: (-15 + 1), so rounding and subtracting a 10 is just easier.

[@liamtorres1134]

Bro i did the same thing, my mum always asked me the 7 th row which (in my head) was the hardest, probably because it was the biggest number with the most amount of odd numbers (i dont count nine because i subtracted the 2nd place to the left of the dot number by the whole number 9*2 = 18 =20 -2, 30-3=27..., in like 2 nd or 1st grade i found out that evey step up you go on the 9 th row you subtracted 1 by the unit place and added onw to the 2 nd plce to the left , was way easier that way), i skipped learning the multiplication tables that way, its more important to problem solve so that they dont get lost when facing bigger numbers.

[@reizinhodojogo3956]

u throught like me, also ×5 is just ×10 and divided by 2

[@jimmydixon9893]

I love the math tricks. Pleasant memories of my father showing me the as I was learning math. Love the explanation of why it works. When I saw the forts graphic of the 4 squares, in looking at the method, everything made sense.

[@tecmath]

Thanks Jim.

[@TaniaJane-yg2gj]

I think you are THE BEST maths teacher EVER!!!

[@tubenube]

Love it! Such a simple a reframe and it’s opened this up with such clarity!

[@tecmath]

Glad you liked it!

[@samnation9887]

I love the voice , it’s smooth and relaxing to me.

[@annenglish2935]

I do it this way... 15×18... 15×10=150 & 8×15=120 = 270... I understand it seems pretty much the same to me... I'm used to my way - seems easier. But your other math videos are eye openers for me, the square root one...have to watch again... I'm 68 and blessed to remember 2+2- HA! Blessings and a Happy Thanksgiving from a grateful California gramma 😄🌴🌺✨🌘

[@idasix234]

Enjoy the way you explain math. Another trick I did for 15x18... 18x10=180 since 5 is half of 10 I just figured (knew) half of 180 is 90 so 180+90=270. Thanks

[@marygagliardi5315]

You are a genius! Love listening to your voice!

[@tecmath]

Thanks...but I'm no genius - just good at some things, like all of us.

[@mrcuppiecupcupmanpantherli8144]

I managed to do the last four questions almost instantly whilst he was writing them down. As in I worked it out before he would have wrote the next one down. And I only used his method for top one - not a flex.

[@stevehorswell2371]

Thanks for the video. I've been fortunate to be able to do a lot of math in my head but I hadn't really thought about how my mind processed it until I watched your video. In your 17*13 example, I see it as 17*10 (170) plus 17*3 (51) which equals 221. Many people can multiply by 17*10 in their heads but, admittedly, many can't visualize the answer to 17*3 in their heads.

[@ricos1497]

I would do that too, but obviously this method is easier for the higher teens, like 17x18. Using your method, 17x8 would be difficult.

[@tecmath]

That is cool... The 17 x 3 part you don't need to visualise... just use the second method. Thanks for your comment.

[@nickmorley1159]

I really enjoyed this. Very easy and clear explanations and I found myself getting it all correct without a calculator!

[@TheRiverAnt]

Thanks for the explanation! Helpful. Not always obvious for peeps to see.

[@tecmath]

Glad it was helpful!

[@benjamindover7050]

TY, the illustration with the times table really helped.

[@tecmath]

Thanks.

[@EmilyLovesTea123]

As a GCSE student who’s awful at math this will probably help me

[@tecmath]

Hopefully. Good luck.

[@akboy47]

im doing calculus 3 and idk why my mental math abilities no longer exists

[@AnyFishWillDo]

I like the method and the explanation was perfect. Thanks.

[@kellyannejones2589]

I really like this.. it’s soooo simple yet I can do them in my head 🙌🏻

[@akamiguelsanchez9985]

As a trainee teacher, your videos have been incredible

[@suzanneedmonds1566]

I love this method, how very cool. I can't wait to share this with students.

[@notgate2624]

That table really made this click. Great video

[@tecmath]

Thanks.

[@phoebea]

This is so helpful and the explanation is well done. Thank you!

[@kylenleo9339]

Well explained and easy to understand, thank you SIR

[@fraso7331]

A great video. I would have explained it through the computing. But it is nice to see it done by geometric like in ancient times. In our german schools that is nearly never used.

[@tecmath]

I've always used the algebraic way... but I like this way. Which do you prefer now?

[@android_m7]

Yo, Thank you So much For Telling me these Maths Trick..Though I am Not Good that much at maths but yeah I understand ur Tricks Thanks ☺️

[@RogersMom94]

Excellent explanation! Very clear. Thanks!

[@keplercuber9155]

Heyy this is really useful, especially the first method. Second one is also much easier than a visualization. Glad I found this channel! Checked out a few of your previous videos, and I am very very impressed

[@242math]

very well explained, thanks for sharing

[@aishwaryam9347]

@tecmath Hi sir I am from Tamilnadu, India ..I just love all the tricks u taught..they are very nice and helpful! Wish you keep growing sir!! :)

[@phayios]

Really interesting to SEE how & why the tricks work. I think that this is a good new formula.😊

[@tecmath]

I think so too! Thanks for watching and taking the time to comment.

[@Heliumz]

Brilliant! Thank you

[@greenfalcon1696]

Thank you for another useful video.

[@242tommyboy7]

excellent times tables trick, it really works

[@Muskan_2616]

Plzz continue with explanation of every trick I like it

[@kuljinderbuttar5398]

wow bro so nice of u very good math trick man!

[@trelligan42]

Very good explanation, the graphical element makes it easier for me to remember. #FeedTheAlgorithm

[@tecmath]

Don't feed the algorithm!

[@lilte3332]

I guess I won't have to cheat😂😅thanks to you

[@ahmeda5394]

انت بالفعل الافضل في هذا

[@yarisngeng7374]

I'm smashing that ugly fat thumbs up button and that loud ringing bell and subscribe button, thanks mate

[@christineb2640]

Wow that box was so cool❤

[@MaJetiGizzle]

For any of these teens numbers multiplied by 20: Add the smaller value’s ones digit to 20, add a zero to the end, and then multiply that digit by 10 and add the two values. Ex: 20 * 16 20 + 6 = 26 260 + (6 * 10) = 320 For numbers less than 10, multiply the ones digit by 10 twice and add the two products. Ex: 8 * 20 = 80 + 80 = 160

[@anthonybost8646]

Love your math keep it up!

[@doubrashair1794]

Thanks for simplifying it.

[@Compuscience-Python-Prog-Exps]

I think you're EXCELLENT!

[@DemoniqueLewis]

Awesome lessons! Never knew this!

[@tecmath]

5 minutes well spent!

[@maxroberts7393]

It worked for me.

[@randlyons7278]

Yes it helps us learn and understand math when we get how the algorithm works. Another great lesson . Yet I marvel at the idea that some- know it all -sharpshooter should hoot about your videos for any reason . I mean seriously, if they don't like your " down under " dialect they should go find something to do with themselves.😁

[@tecmath]

It's just the way it is. But thanks for your kind words

[@WillN2Go1]

Excellent explanation. That's the Babylonian (or Egyptian) field squaring method. I read in a book where a guy was hired as a computer quant on Wall Street because he was asked in the interview if 2499 was a perfect square. If you understand the 'field method' (don't know what it's called) you immediately spot 50^2 = 2500, so -1 = 49 x 51 = 2499. Should I have been working on Wall Street all this time?

[@chocolateangel8743]

Teaching people WHY algorithms work the way they do is how math should be taught. It helps the algorithms used to solve problems make sense -- especially for those of us who do math based on logic (rather than memorizing steps) - never worked for me. I view math as a language, and in order to successfully execute any algorithm, I have to understand what I'm looking at.

[@tecmath]

Thanks for that input. I hope you liked the video.

[@chocolateangel8743]

@@tecmath Yes. I love me an area model. Besides numerical multiplication, I like using them for multiplying/dividing polynomials, Completing The Square on Quadratics and the Sum/Difference of Cubes.

[@chidinmauzodike7144]

Smooth. Thank you

[@ChosenMan37]

Can you do a shortcut on quadratic equations again. I tried doing them but keep failing or going wrong horribly

[@aussiehardwood6196]

Very clever

[@dineshchavda8789]

Why they do not teach this at School? Impressed

[@O.Reagano]

haha I've always done the second trick, I wasn't taught it I just learned to do it that way.

[@thechef6969]

If you could figure out an easy way to take the cubic root very fast, I would love to see that. I would also be interested in some more calculus videos!

[@Compuscience-Python-Prog-Exps]

I like my good old-fashioned FOIL method much better. I do math sideways, never in columns. I use brackets so I can clearly maintain it all in my head. Columns never ever worked for me at all. I dived the same way, I short divide, so I can maintain what I'm doing.

[@N_Luffy223]

Tysm it work I will sub to you

[@nmklpkjlftmch]

Was the 13 X 14 = 184 in the thumbnail bait to get people like me coming to watch and comment? I've watched a number of your previous videos and they're really informative.

[@frugalbirders7416]

Your videos are both fascinating and useful. Please don’t use insulting clickbait tricks like 13x14=184. It cheapens your brand.

[@tecmath]

No. It was a genuine brain fade! Thanks for alerting me.

[@tecmath]

No. It was me writing up a thumbnail brainlessly! Thanks for alerting me.

[@tecmath]

Funny thing is there was an uptick in views when I put that thumbnail up...hmmmm...

[@nmklpkjlftmch]

@@tecmath I thought it might have been an accident, just writing the 4 from the end of the 14, seeing as it was correct in the actual video. Anyway, your channel is helping to keep at least one brain a little more active in this age of calculators and computers.

[@littlefish9825]

One thing I find helpful is to break everything down until you get an intuitive sense of how it works. Everything in math can be broken down more and more to make it simpler and simpler. Break 2 digits into the tens and the ones, temporarily completely tear apart the equation of you have to. Once you can do that, each part is individually a trivial task, so then just put it back together. You really don’t need to know how weird math stuff works with gross numbers, all you need to know is how basic functions work and how to break a number into manageable pieces. Once you understand this, you’ll understand that this is like 90% of algebra.

[@tecmath]

That is an awesome comment.

[@KingFoxiFox]

thanks

[@dorischoo]

I like it. Is good works for me

[@MrSpidey1970]

Nice

[@yermom7514]

This is what I do: Let's say we are doing 14 * 18. Which number is closest to a round number? 18 is 2 away from 29, 14 is 6 away from 20. I will pick 18. 14 * 18 turns into 14 * 20 14 * 20 = 280, since 14 * 2 = 28 (add the zero) 2 * 14 = 28 280 - 28 = 252.

[@tecmath]

I like that method. Thanks for sharing.

[@SKVL1317]

U using x × y = ? X = a+b Y = c+d So ~ (a+b) × ( c+d) = ac + ad + bc + bd = ?

[@redkaiyt2308]

tnx man

[@parmelar]

Love you

[@lucienpetrus6906]

Luv it

[@kevinashley478]

So, I have always been pretty good at math. I can do math in my head and do that by using what I have always called my "mental chalkboard". I just see a blank chalkboard and I "write" the problem on the board and figure it out. I never understood why my kids were struggling so hard with math, and sadly I would get frustrated with them anytime I tried to help them. It wasn't until one day, during dinner, my wife asked me why I was getting so frustrated and I said, "math isn't hard, so I don't understand the struggle here. It's add, subtract, multiply, or divide. Why won't they just use their mental chalkboard." Yeah, I am aware of how dickish I sounded. My wife then gave me a deer-in-the-headlight look, and so did my kids. They all asked what was I talking about. After explaining, my wife said that she had no clue what I was talking about, and neither did my kids. It was at that moment that I realized, that not everyone could do that. I had gone 30 years thinking that everyone could do math like I could. After that conversation, which had me apologizing repeatedly, I was able to help my kids with their math without getting so frustrated so quickly. Thank you for making these videos, as I may have better patience, but I suck at teaching. I know how to do things, but I don't know how to explain them so that other people get it. I will definitely let my youngest daughter know about your videos and have her share them with her friends that might be struggling with math. Whenever we were in school, we have all said, "when will I ever need to know this in everyday life?".... And it is a fair point for most of school. But math IS something you will use every day of your life. Thank you for doing something that I can't.

[@limporgyuk]

A few days ago I saw a rig that’ll pull that tanker

[@Hashimrea]

my brain has exploded ;] bc of all the maths

[@tentontoby]

Great tip! but only worked for numbers up to 19, not to 20 as mentioned...

[@ThatBrubakerFellow]

Start counting at 0. 💩

[@tecmath]

You for me there! I also missed all those decimal numbers too...

[@Compuscience-Python-Prog-Exps]

(10+7)(10+3) = 100+30+70+21 = 100+100+21 = 200+21 = 221

[@ronaldzakoc8121]

G'day mate: just like to say, lm crap at maths. From 1969 when I was 7 I was called a slow learner, so all the class did not care about us .most of the teachers did not give a rats ass . I hate to say it to this day my maths is crap . I do like how you do it with numbers 👍

[@tecmath]

Thanks mate. I'm sorry that was your experience - it seems sometimes teachers can do that. It's good to see you on youtube chasing this up. The best bit - you can take all the time you need and not worry about passing some contrived test.

[@ronaldzakoc8121]

@@tecmath Dam strat mate 🇦🇺👍

[@Compuscience-Python-Prog-Exps]

What you are actually doing is FIOL work?

[@sbiju7235]

Great...

[@Mike2infinity]

I don’t get this channel because I have my IPhone at all times, “Siri, …” boom answer!

[@tecmath]

Ah. The other type of comment I get!

[@Mike2infinity]

@@tecmath ah tecmath just kidding, great vid, keep up the great work! Also what’s a fun way to learn the multiplication table? I keep printing blank tables for some of my co-workers kids but I’m seeing no progress, so before I give up and say “good luck kids” any advise? Thanks Mike R from California

[@tecmath]

@@Mike2infinityThis sounds controversial but here goes... I didn't trust my kids primary school teachers 100% so I taught my kids the times tables... in the order 1, 2, 5, 10, 3, 9, 4, 6, 7, 8. We didn't move onto the next times tables until the other ones were mastered. I did this where we would start by reading them together 2 or 3 times...I then used an app where you could choose the times table. It had a timer... and the challenge was to do a times table in under 30 seconds...keeping it fun and light. I'd also write up lists of mixed problems of the times tables covered so far... including division. All this... 10 minutes a day...unless they wanted more. Once say they'd mastered the 2s, we'd move into the 5s, and repeat (but occasionally including the earlier tables in!). Hope this makes sense. I'll go further. The problems in this video we used to do like this... I'd call out a problem... (say 14 x 19) and the kids would dive in the pool (we were on holiday) and try to get the answer before they surfaced - but you can modify this (hold breath, whatever, but keep it light and fun).

[@dcraexon]

👍

[@nunyabiz6925]

Thank u for busting out the distributive property . I’m too dense to get the answer u left for kris p. Bacon. To be fair it’s 1230 at nite , but I’m sure it had to do with that diagram

[@staceyjohnson4513]

I understand how do you this if the 10s digit is the same. What if it’s different 10s digit? For example, 26x42

[@tecmath]

Me? I use a different technique!

[@staceyjohnson4513]

@@tecmath Have you already done a video on it? If not, would you share the technique?

[@staceyjohnson4513]

Never mind! Found it!

[@harryatkinson5980]

Yes

[@SotGravarg]

It's the point of magic does anyone know a magician that explains how his magic tricks work? No! That's why as long as it works you don't have to know how.

[@cindymcdnld]

14x7 = (10+4)7= 10x7 + 4x7

[@Offical_Comedic_Relief]

I only have one problem w you- Your a Geelong supporter- Better then Richmond i suppose

[@tecmath]

How do you know I go for the mighty cats?

[@Offical_Comedic_Relief]

@@tecmath ur first video someone’s singing the song

[@julekacouffaine5372]

1:04

[@ronanmendoza632]

How about 6x6??? It wont work.

[@AntonydenDulk]

People are not good at following instructions 20k views and only 145 comments :'(

[@tecmath]

Thank you for noticing!

[@victorriaxo]

am i the only one who is confused why the thumbnail says = 184 instead of =182

[@tecmath]

Sorry for the confusion and thanks for alerting me.

[@Brukrex]

hello

[@tecmath]

Hello. How are you?

[@xxxmikben]

Don't you listen to the naysayers tech math. You can lead a horse to water ... 🤯

[@cypherknot]

That looks like FOIL (13)(14)

[@tecmath]

That's exactly what it is.