Fast Mental Multiplication Trick - multiply in your head using base 10

[@AussieAnnihilation]

amazing, im learning more in 1 hour on your youtube than i did throughout all of my schooling life.

[@Lodin03]

true.

[@CorbsVids]

Well you're not...

[@gamershunch2099]

how?

[@anjellalo972]

@@gamershunch2099 because he's been binge watching this guys videos? Also I think he means the stuff he remembers from school, not what he learned

[@gamershunch2099]

@@anjellalo972 he should have paid a little more attention

[@Beevreeter]

Fascinating but my calculator might feel rejected

[@natriac.6092]

Well let it rest sometime I think it needs it.

[@cringeyvideosforfun3266]

Lol

[@vikocoptic]

😂😂

[@lucasmumo3470]

😂💀

[@chrisleal6321]

Your calculator is the reason you're a grown up watching videos on how to multiply 2 digit numbers.

[@dave9456]

I really struggled with maths at school, and managing to get ungraded in my maths exam, fast forward 40 years to now and I can confirm my confidence has 100% grown

[@bogdanescu86]

Pretty cool trick. I've always used the method of splitting the multiplication into 2 easier ones and it worked fine for 30 years and counting: 15 x 13 = 15 x 10 + 15 x 3 = 150 + 45 = 195

[@jasonthomas2908]

This is also how I do it.

[@lijokjohn2001]

many years ago ..my father taught me this splitting trick

[@devisnomiac212]

I do the same

[@richb7414]

15x13... 15x15 - 30

[@josephmurphy7480]

Awesome!

[@somchitleang1001]

Where's them math at?! Not scared of you anymore! Now I can pass this on to my grandkids. I'm gonna sound like a genius. YES! Thank you very much.

[@kenyonbissett3512]

Learn it by high school and a few big words, you know bigger then the 4/5 letters that are in every sentence these days, and people will think your smart/intelligent for the rest of your life. Tricky, tricky. Just be casual about it. Throw in occasional comments like “caught thinking outside the box again” or shrug your shoulders when asked how you do that. Or, offer to teach them. I’ve fooled people for 50 years. After awhile people just assume.

[@jalle88]

My god this is brilliant. My middleschool class is gonna love this. Thanks!

[@aronwomack4948]

cool

[@slimepcd]

I’m in middle school to

[@boiifyoudont6113]

It’s just distribution. 14*13 in his method is just (10+4)(10+3) he just writes it differently

[@isaiahjamesimmakingthiseas8018]

jalle88 you’re in high school now

[@Comandobunny]

@@isaiahjamesimmakingthiseas8018 ...I'm pretty sure that was a teacher, mate.

[@cottoncandy113]

Why the heck don't we learn this in school?

[@MrMicangel23]

Coz teachers don't want to get embarrassed by us getting the answer before he gets the first digit

[@mikecromaticm2896]

Hive Atlas Because they want you to learned the basics ways thats been handing down to us for 1000 of years.

[@maryblue75]

But i would like an explanation about why that works...?

[@Joel-xm6tb]

Mike McCarthy Cavemen Style

[@ilyasseboudjemline2039]

That's so true The reason behind that is that they just teach u whats in the book that the government gives for schools so they don't teach u the exiting and easy ways to do it.

[@BeardyBaldyBob]

What the hell?! All the way through high school and 5 years at uni and I never was shown this technique?! 🤯 It's so simple and intuitive!! I'm actually kinda angry I was never shown this at school.

[@flamemaster4594]

17x15 = (10+7)x15=150+105=255 That’s what they taught you! Way better to remember

[@meekawolff]

I have a nephew who hates math because he says it's too difficult. I love math because I was lucky enough to have an excellent math teacher who made learning math fun. You remind me of my math teacher. I am positive that once my nephew watches this video he won't hate math anymore. Thank you 💕

[@turbotime7605]

Brilliant! I've had to brush up on math skills for an aptitude quest and your series of videos have helped immensely.

[@trillazgurlps]

I want to thank you so much for this SIMPLE method, I suffer from mild dyslexia & im not a wizard in multiplication or division, I couldn't figure out for the life of me how I could do every other piece of math in the book in different areas yet my memory wasn't wired to deal with neither operation (im in my 2nd year of college). It was how I was trying to handle it, outgrowing lattice, & tired of the egyptian math, so again I want to thank you not just for me but for ALL OF US because there are soo many of us that feel inadequate being some kind of smart yet having issues handling these two operations. Its truly a blessing to share it regardless of the history behind it! :-)

[@sathyaramesh6978]

Dslexia is a myth there is no such thing its all n our head

[@chynthiayani8419]

Please continue on what you're doing, do not stop! Its really helpful thank you

[@realtoast7036]

Yesterday, I had a 2-hr drive home. Spent most of the ride mentally working this method in my head with random problems and checked results with Siri on my watch. Funny how time flew. I was thoroughly entertained! With practice, it becomes easy to immediately get that 10x without any real thought, and also easy to instantly generate the product of the two "more than / less than" numbers without much thought. The longest part is the final addition / subtraction.

[@mickystam521]

Everyone: Eight Tecmath: Aight

[@Bluwoo-ct6wz]

HAHAH

[@P7.001]

We need more people like you in our society. Keep up the good work.

[@spongiform]

I have always been truly appalling at multiplication - this is revolutionary for me. Thanks so much!!

[@Tei_022]

I seriously should’ve been taught this in elementary school. I learned more in 10 minutes than I did in 3rd, 4th, and 5th grade.

[@emiyakiritsugu6329]

hey there, please be kind and help.….iam now 7th grade , i fear my study a lot bcoz i mostly depend on memorization, i barely can use logic or i suckk, i am not good at other subjects except math....i love math its fun as i am killing and torturing monsters in game.… so..… is it okay if i learn these genuine knowledge besides my studies

[@_aaryanmore]

@@emiyakiritsugu6329 hey don’t worry you are in 7th grade only. It is okay to learn this kind of stuff

[@emiyakiritsugu6329]

@@_aaryanmore thanks for telling, 🤤

[@SortaFresh]

@@emiyakiritsugu6329 let me tell you right now. It is okay to learn for fun but DO NOT SUPPLEMENT THIS FOR UNDERSTANDING OF MATHEMATICS. Tricks don’t lead you anywhere. At that point you are computing like a computer. As u get into higher level math many idiot teachers will try to get you to memorize things without explaining the reasons why they work. The same applies here. It’s okay to have fun or have this as a party trick, but unless you understand the fundamental reasons behind it, you should never use this as an alternative.

[@emiyakiritsugu6329]

@@SortaFresh iam gonna cry 😱😨😭from your huge pressure but i dont use this trick for anything but iam bored in lockdown so i learn this bcoz i want to do this in my head otherwise i will do it in general way thank u for scolding me , it took u forever to type

[@mahtinown-eel]

I’ve done this my whole life without being taught this, it always seemed easier to me to work out equations this way.

[@Rose-oz6lt]

Can I ask, why it works? Like I understand how to do it but why does this tactic work

[@theracingpotato3124]

​@@Rose-oz6lt Ill try to explain it for you. I suggest a pen and paper because this proof is hard to explain in words. Let’s use the example of 56 x 48 = 2688 In this alternative method this would become 54 x 50 +(-18) Let’s turn turn this method into algebra Normal way of multiplying is F x G = H (Equation 1) In this alternative, you use a ‘Base’, which ill call B In this alternative method, You find the difference ( for F the difference is D and for G the difference is E) between the Base (B) and your numbers (F and G). If ‘ F=B+D and G = B + E, then B = F - D and B= G-E (Equations 2) Now we have two equations that both equal the same value, which is B, we can make them equal each other: F - D = G - E (Equation 3) Rearranging F + E = G +D (Equation 4), this equation he says in words at 2:12 to 2:25 With some more rearranging G = F + E - D Now lets bring our original equation F x G = H and lets combine with our previous equations: F x (F+E-D) = H If we Expand: F^2 + FE - FD = H. (Equation 5)Remember this equation as we will come back to it. Now using the method. The first step is to do Equation 4 so lets use F +E (In this example 56 +(-2) = 54 )The second step is to use the Base (In this example is 50) Which we know, in equations 2, is equal to F - D. Let’s multiply these together: Algebraically: (F+E) x (F-D). Expand the brackets, F^2 +FE - FD - DE = Some value (Equation 6) In this example: 54 x 50 = 2700 Now realise something? Equation 5 and Equation 6 look similar. The only difference is the Equation 6 has -DE and Equation 5 doesn’t. What is the last step? ADD DE to equation 6, thus making it equal to equation 5. That is the proof.

[@CDXLIV444]

@@theracingpotato3124 shouldn't it be 54×50 minus 12 for the alternative, not 54x50 +(-18)?

[@isaiahriordan3159]

I have no words to explain how much your videos help me, thank you.

[@ggheat4975]

For 15x15 you might notice it’s a perfect cube, there’s an easier way of getting to correct answer for squares that end in 5 Say you have 25^2 when we have any perfect cube that end in 5 it will end in 25 always so what you want to do is just take out 5 because we got our first two digits (25) you now multiply your remaining digits (so 2) by one number above it, so 2x3=6 now you put that in front of your 25 which gives you 625 this works for any square that ends in 5 35^2= 3x4=12 add infront of 25 is 1225

[@XAE_A_Xii]

i knew that from my school years, don't know how i got this as well or someone showed me

[@robloxmegamaster5916]

This is so genius

[@sadsader100yearsago9]

Yea, I did this back in the 4th grade

[@erggish]

what he is actually doing is writting: (a*b) = (10+X)*(10+Y) = 10*Y+10*X + X*Y + 10*10 = X*Y + 10*( [X+10] + Y ) = X*Y + 10*( a+ Y) or if you add the 10 to Y, you will get: X*Y + 10* (X+b) However I find easier to do the other way (since adding 100 is always much easier): 10* (X +Y) + X*Y + 100 So for example if you have: 14 * 15 .... X=4, Y=5: 10*(4+5) + 4*5 +100 = 190 + 20 = 210 This idea can be done in other "bases" if you call it that way... instead of writting a=10+X, b=10+Y , you can write a=100+X , b=100+Y the result will be almost the same: 10000+ XY + 100*(X+Y) base*base + XY + base*(X+Y) So in base 20 an example would be: 25*26 = 20*20 + 5*6 + 20*(5+6) = 400+30 + 220 = 650 an example containing different "bases" (1000, 300, 100 respectively): 1371* 1420 = 1000*1000 + 1000*(371+420) + 371 * 420 371*420 = 300*300 + 300*(71+120) + 71*120 71*120 = 100*100 + 100*(20-29) - 20*29 = 10000 - 900 - 580 = 8520 going up: 371*420 = 90000 + 300*191 + 8520 = 90000 + 57300 + 8520 = 155820 going up 1371*1420 = 1,000,000 + 791,000 + 155,820 = 1,946,820

[@theolla840]

Chris X Thanks very much for posting this. I'm less interested in learning arbitrary "tricks" to solve problems, and more interested in learning the real math behind the tricks. This was exactly what I was looking for. All I was taught in school growing up was to memorize patterns to solve problems, like those in the video. But you never learn WHY you're doing it. The way you've shown can be customized based on different problems and shows more of an understanding with manipulating numbers. Thanks again.

[@jonathanrees2449]

I agree. Thanks also.

[@trollgod4911]

Lol your way is far to complicated and not practical...fail

[@erggish]

Troll God said a the dumb face.... keep on whining for some attention! common! you can do it!!! beg and lie on your knees..beg for more.

[@iver7694]

Troll God it's actually not

[@christianyellic3394]

Thank you so much! ♥️ You have no idea. I was traumatised as a child, sometimes physically, because it was drilled into me that I’m a nobody if I can’t calculate. I made sure I never did the same to my kids and now they thrive. This has helped me immensely and made a joy of maths. Thank you 🙏 😊

[@spiralnapkin]

To all who think they learned more in this video than they ever did in school: no you didn't. You learned a faster and more efficient way of doing one math concept. Yes, it's super helpful, and I love these tricks, but you can't get to the point of doing these tricks without knowing the basics, which you do learn in school. These are meant to supplement and quicken the process, not substitute the basic concepts.

[@Askcyeda]

Thank you - your videos are making our "Math Year" homeschooling much easier.

[@GlitchTheF0x]

"What is 14 x 12?" I am immediately lost.

[@butt.]

14 x 10 , add 2 more 14's. 140 + 14 + 14 or 140 + 28 = 168

[@td5604]

Using base 10: 14×12 14 is 4 more than 10. 12 is 2 more than 10. 4. 2 14×12 So, 14+2 (or 12+4) = 16 Add 0 to the end, making the number 160. Then, multiply 4 by 2, which equals 8. Finally, add 160 to 8, which equals 168. I hope this helps. :)

[@Fab24hdumans]

For his “8x17” simply 8x10=80 then just 7 (from the 17) multiple by 8= 56+80

[@DiepNguyen-ce4hq]

@@@td5604 I really love you saving me from big headache =)

[@td5604]

@@DiepNguyen-ce4hq You are welcome! :)

[@anne9576]

Secret is to know your times tables inside out as we were taught years ago in school what a great channel ive found 👩🏼‍🎓

[@bmwkamal]

I am watching your amazing videos and still cannot believe how myself a growup has never heard of this kind of formulas(ways of calculatimg)? Are these new discoveries in math or what? Amazing

[@MsAbrar43]

I felt smart at the beginning of this video then I got lost in the middle of it lol I think I need to do more practice!

[@yousefhashim797]

Your better than all my school teachers stuck together!And these tips and tricks are really useful

[@rosinatricanico7729]

Amazing trick! Some people call it "the distributive law" though. I don't know if people generally talk about that at school..

[@leemonk384]

My son used Kumon for math and it's his favourite topic and when I was working with him I always used to find 'tricks' to do math. I was adamant that there was always a 'trick' to math.... you just needed to find it. Your videos are amazing and I'm only frustrated that I've only just disovered this channel. Just subbed!

[@deenique3112]

Where have you been all my life🤦‍♀️......thanks alot!!

[@shriyashaw1430]

OMG U HELP SO MUCH. I THINK OUR TEACHERS ARE PART OF A SECRET EVIL SOCIETY TO TORTURE OUR BRAINS. WHY CANT THEY TEACH US THIS

[@mjcard]

Shadow 88 teachers don't know much. all they know is if someone's feeling get hurt or if you're a racist.

[@nashparbhu]

Curriculum.

[@karaciinali4199]

Yo

[@EternalShadow1667]

mjcard not sure they even know that

[@realblacksknowthetruth1519]

Only if they follow the syllabus that they're taught! Which is why my mother got fired she never followed what they told her, as a teacher and happened to be one of the greatest not only special education but honor classes for 8th graders, she gave all students inspiration to understand learning she was very creative and everyone loves it

[@ncjackson1958]

Thank you so much for taking your time to make this incredible and eye-opening video!

[@MyExpertAccountant]

Wow.. took 41 years to discover this. Damn school is a wsste!

[@yeetub]

My calculator is gonna feel rejected like my abandoned counting fingers.

[@Gabriellazoeofficial]

God bless you, I don’t know what teachers at school but they don’t make it any easier for students to understand. You are an angel from heaven to help us 🙏🏾🙏🏾

[@barfyman-362]

here's how this works geometrically. picture a rectangle 14 high and 12 wide. take two columns off the side now it is 14 high ten wide. take the piece that's 2 wide 14 high and turn it sideways and put it on top of the other rectangle. now it is 16 high and ten wide, except the top two rows which are 14 wide. since they are 4 pieces longer than the others they stick out 4 spaces and there is two of them, so you have 16 high 10 wide plus a little piece that's 4 wide and 2 high, it's easy to see it is 168. this makes it so the "trick" actually makes sense.

[@Lustas]

Psychotic Ape Thank you mate! Now it makes even more sense to me.

[@ericsilver5603]

Splendid! Pythagoras had much the same idea. Thanks for pointing it out

[@payalgupta6332]

Ko 555

[@100percentgradeA]

They should do more geometric examples like that in school

[@ivettemaldonado-mora6668]

This trick is awesome and I'm in 4th grade! I'm sure I will get good grades in Math

[@edwardcortez6662]

Lucas Games2193 There will be more to it once you go to middle school and high school. Everything won't be just multiplying numbers. But it's still a good idea to know how to do this.

[@gameupplace184]

this is the first time ive heard of this. Ive shouldve known it when I was WAY younger

[@camic7324]

This boy just learned how to math he's not suppose to know for another two years in his head. Why are you criticizing him? It seems to me as if he has a+ parents if instead of looking up dumb youtube videos he's learning maths and being passionate about them. You're getting riled up by a 9 year old.

[@asianwarrior1178]

ten tor let a kid be a kid

[@najaminayat9596]

lol lol Lol n 6wtyck4n

[@ac0SE]

this is the second video that blow my mind over the past 2 years

[@kolowar6600]

Wow just wow. You just taught me something I haven’t been able to get my head around for 13 years of education in the first 2 minutes of your KZbin video just wow

[@minatonamikaze1989]

Thank you for sharing this techniques. It helps improve my skills in math. :)

[@nooralhudasaad1209]

thank u so much man you are a genius i hope that good things happen to u☺

[@spencerbixby7819]

I figured out base 10 multiplication on my own, working in the trades. But in the case of 14x12 I will do (14x10) + 28 Or 15x15 = 15x10 + 75 Not very convenient for larger numbers, so thanks for this method!

[@lampy5490]

5 minutes into the 1st video, and already this has helped me! Thank you!

[@terryberry12]

OMG, THANKS SO MUCH! THIS VIDEO IS SO USEFUL! WHY DONT WE GET TAUGHT THIS AT SCHOOL? UR AMAZING!

[@cameronp7694]

Bob Ross is back to tackle math!

[@delightburberry7700]

Another suggestion you can using another method:-15×13. 15×10=150. 15×3=45. 150+45=195.

[@toytrooper7309]

Thanks

[@delightburberry7700]

@@toytrooper7309 No problem.

[@anne9576]

Omg im nearly 70 and youve taught me something I couldnt grasp in school thankyou im really enjoying your videos 🇬🇧

[@Dontcopit]

I taught this to one of my Oppos on my war ship, a young fella, about 19. Seriously he was struggling doing sny of his times table. He was out performing me within about 3 hours. All I used was Speed Math for Kids. Nice to know your old. I have to spend a day or two every 6 months just practicing. I also had a Science teach tell me it would never work, until I proved it to him.

[@sultanal-issa9844]

thank you so much for this video, you're awesome.

[@JeremyEricson]

7:43 And that's a great price!

[@arjunmanoj8522]

Pooods

[@no-body-nobody]

399

[@delightburberry7700]

15×15. 15×10=150. 15×5=75. 150+75=225. 9×18. 9×10=90. 9×8=72. 90+72=162. 14×13. 14×10=140. 14×3=42. 140+42=182.

[@chipan9191]

for the 15x15 you can just take 1(1+1)x100+25 to get your answer. 1 time 2 is 2, times 100 is 200, and plus 25 to get 225. that method works when squaring any number ending in 5, just use (10x+5)^2=x(x+1)100+25.

[@iLoveTurtlesHaha]

I never memorized the regular times table to begin with (my teacher use to hit me to learn it so I am traumatized). Even though I understand how to do it this way, I'm still slow at it because I have to do the lower multiplication first. Eg. 18x18 ... I have to add 18 to 8 by hand then figure out what 8x8 is then add it to the first calculation. By the time I get to 8x8 I've forgotten what 18+8 is. FML. The journey to getting better at this is most likely a long one. I hope I make it. :(

[@كُلُّنَفْسٍذَائِقَةُالْمَ-س6ع]

WHERE DO YOU LIVE😢 that is child abuse😭😭😭😭😭

[@mr.zyplexer6983]

@TatTvamAsi. Pay no attention to what Ali K says. Math anxiety is a real thing but you can overcome it. Just make math a regular part of your daily studying and don't get anxious when you don't understand something right away.

[@cale378]

If your teacher hits you you should sue the school or her individually, when she hit you I hope you asked to speak with the principal, talk to your parents about it and the right decision would be to leave the school, if they do nothing call someone, or a certain company to help you in this situation. Talk to the principal buddy hope I helped

[@FMD023]

TatTvamAsi likewise. I was taught the way u were taught. We might calculate slower but we will KNOW how to solve the answer without “remembering” math is logic and a universal language. Once u understand the basics and fundamentals, u never forget as to remembering certain shortcuts or techniques

[@quarantinelife.]

Same. Also my middle school math teacher was terrifying and would make fun of students in front of the entire class on a daily

[@Dain_42]

Life saver, thanks so much!

[@assmaaalsatouf9793]

Thanks so much this is really helpful!👍🏼

[@HeySonia]

This is the best trick i’ve found and i’ve tried some before! Thanks!

[@carsonmorris127]

This is revolutionary! Why is this not part of the fundamentals we learn in elementary school. We could actually save time on the ACT and SAT by my even needing a calculator for most of it

[@mrchri5topher]

thank you so much for this

[@UKnowBo]

Awesome, it’s just that you’re 50 years too late. Wish I had you for a teacher- yesteryear. Thanks mate.

[@just_cubes6101]

This might save my life since im taking advanced math next semester (have to pick two out of 3 classes for advanced courses and math is the smaller evil)

[@shelleythistleton4935]

How does this build number sense? I am very wary of “tricks” that students learn but they have no idea how or why they work. Students need flexibility of thinking in my opinion.

[@rrssmooth6643]

My teacher was teaching that, but he went so fast, so I had to work it out differently. Now I get what he was doing.

[@anxiety5393]

you made me love math as someone who cant remember for the life of me. aka dyscalculia.

[@miguelkiyot8028]

i did not understand the 15x13 got 180 why did you put zero please help me :(

[@eddiemd7868]

miguel kiyot 15 + 3 = 180 then 3 x 5 = 15 then add 180 + 15 = 195

[@juvyalberca4489]

You should give a mini quiz in the end of your videos so they can use what they learned

[@arimas1977]

In 5 mn I learnt more than In A year ! Unbelievable ! Merci beaucoup !

[@delightburberry7700]

19×21. 19×2=38. Add the 0. 380. 19×1=19. 380+19=399.

[@wii3willRule]

Amazing! I wonder, why does this work?

[@daniyalk713]

hey thanks for making this video i really appreciate what you doing i also use the base of 10 concept i somehow developed it on my own for myself i wasn't taught this way but the multiply idea is a great addition i never looked at it this way, your videos are awesome

[@Aimsey4Guqqie]

dude… THANK YOU SM!! school is starting up and i am going into year 6 so i have to learn roots but the fact is i dont know time tables..

[@yusef4440]

Yes! An Australian!!!

[@ambera6650]

he sounds like a British person

[@yusef4440]

not really...

[@chrisashby32]

Definitely more Australian

[@ImaRataholic]

Kiwi, he says eh!

[@yuriaihara704]

no! its Jermaine from flight of the chonchords and he is from New Zealand

[@keyshajones5352]

+4 +2=168/8 autosourceP a=b (8/true) ap source=+energy H n.d>.H.3

[@TheEpicDartfish]

This trick is amazing, I wish they taught us this in school! I got the hang of it within seconds!!

[@wilescoful]

Love your stuff. Keep it up

[@Desyphe]

How is this not being taught in school but common core garbage is

[@lorrainehutton3527]

CHRIS PALM: What is "common core garbage?"

[@JustTheaMyself]

I know this will be burried but with questions that invovle one didget and a 2 digit i do this- Ex- 6 x 17 first do 6 x 10, then do 6 x 7 and add them both or also shown as (6x10)+(6x7) so 6 x 10 = 60, 6 x 7= 42 60 + 42 = 102!

[@1wholovestrees]

I’m nearing 70 and I’m enjoying these videos.

[@mansibhandari752]

HEllo techmath, i want to know why you add 18 wid 0?

[@Nobody-hc1rw]

Because you are using 10 as a base. 14x17 (+4) (+7) == (14+7) x (17-7) or (17+4) x (14-4) == 21x10= 210 + (4×7) = 238 He simply "adds a 0" because doing the x10 as an extra step is futile.

[@saneejzubdah]

it is very good for teachers as well as kids

[@cheyannerainbow6402]

you're a genius, you're teaching doctors

[@halfdanerik7874]

Wonderful tips. Thanks for sharing. Its a shame there was no KZbin back during my school years back in the in the 80s and early 90s. :(

[@jamalneri79]

your hacking a numbers nice

[@kingaragornii9940]

lol

[@breadcredit7861]

His voice makes learning easy

[@tecmath]

And sleeping to the dulcet tones of math...

[@goodguy4900]

You are my teacher from now on.

[@gitanjali3112]

God bless you. I have dreaded multiplication all my life.

[@doomsdoomsday6014]

Wow thank you! I have watched a few others on this, but I really like your method! I will definitely be using it in the future!

[@jamalneri79]

your a math geneous

[@XAE_A_Xii]

when yoou multpily two of the same numbers ending with 5 (25x25 for example), take first number (2) and multiply it by itself plus 1 (2 x (2+1) =6 ) add 25 at the end: 25x25=625 75x75= (7*8) & 25=5625 15x15= (1*2) & 25=225 and so on

[@dannie3117]

Well done. Using my brain instead of a calculator. You’ve put a smile on my face

[@maliciouscompliance6489]

Hall of Fame life changer. Thank you!

[@lamont9096]

This is life changing stuff man… If I watched this video 9 years ago I wouldn’t be in the place I am now. 🚬

[@omarbadr9424]

Anyone in 2019?🤣

[@farhadjawhar4055]

Niiga

[@jovairiyanoore3148]

not funny anymore

[@farhadjawhar4055]

@@jovairiyanoore3148 lmao

[@angelwiththelegends5627]

Yeeeeee 2019 year o learning

[@jovairiyanoore3148]

farhad jawhar that’s racism u can be fined for that schmuck

[@adrianc5666]

I do it slightly different. I thought when you said “base 10” it meant a technique that I’ve used since I was a teenage to multiple large double digit numbers in my head. Let’s say 16x25 10x25=250 6x25=150 150+250=400 And larger numbers. 45x53 10x53=530 4x530=2120 5x53=265 2120+265=2385

[@onlinemathsexpo]

This is marvelous. Thank you sir

[@vijaynandwana4289]

Thank you for sharing this trick with us.

[@riverofblood4362]

Getting ready for the PSAT, and I need these methods for fast solving. Thank you!

[@textingpuppy751]

why do u say bice instead of base? but great video!

[@jamespradhan9055]

Jesper Locher South african!

[@ad8369]

It is all in the British accent

[@rio20d]

poly pony its Australian accent

[@textingpuppy751]

thank you i think i got it:D

[@MrJordanT]

why wasnt i taught this in hs? lol