How to mentally multiply big numbers

Multiply big numbers in your head!
And it's easy champions!
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[@TVS...l-_-l...]

Once again Tech math is Back with another Amazing Trick.

[@nilanjandas6928]

6:49 subtraction would be 408-24 = 384. We wanna make your errors in the last problem known to you so that you can rectify it. Despite of it, this video is one of the best!....❤ Respect from Kolkata, 🇮🇳...!!

[@erectilereptile7383]

exactly I thought I was tripping for a second

[@IsThatYouShrek]

No other comments seem to have picked up on this

[@ChimiUdeh]

He really is a good teacher and since I’m going to the 5th grade he’s going to help me with my education

[@gamerguy-dq5sf]

This is too hard to contain mentally. But good vid

[@willbedone888]

Feeling cheated in the name of having to show your work, math was made a tedious chore, always felt trapped in a classroom. When its the answer that was important. Simplifying would have aided progression. Bless you

[@ChimiUdeh]

This is the most helpful maths I have ever seen

[@arunarvind7195]

Thank You

[@PeterMortensen1978]

What is going on here 🤯 408 - 24 is 384 not 380, but the outcome you get is corret, what is happening 😂?. I am here to learn so dont judge me😋

[@farzad_khan_bakhtiari]

The reason why it works is that he makes a second mistake to cover the first one. 380 x 50 = 19,000 not 19,200 as he claims. 19,200 is the product of your correct difference of 384 times 50. That is the reason why the final answer is correct.

[@PatVMurphy]

You are right Peter Angelino, I was working this out in my head, I thought I was going well, then he made that error and *still* got the correct answer and lost me. Thanks for explaining Farzad, I'm not going crazy. 😜 Josh @Techmath can you please either correct this video or delete it? It will confuse people and potentially damage your stellar reputation.

[@PeterMortensen1978]

@@farzad_khan_bakhtiari thank you ma man! 👌 I totally lost it, and thoght i was just not right in the head😂. Again thank you👌

[@PeterMortensen1978]

@@PatVMurphy glad i am not alone in this😂👌

[@shadow15kryans23]

i thought I was going crazy at first XD

[@tonybarfridge4369]

Also 34x152= 30x150=4500 (+4x150+2x30+4x2) =5168 47x408 ~ 40x400=16000 (+7x400+8x40+7x8 ~3176)=19,176 😉

[@dontukme]

Sir How do we solve for 96*532?

[@SpaceWithSam]

Amazing trick as usual sir!

[@242math]

neat way to multiply using rounding, thanks for sharing this easy method

[@FatenElAli24]

Love ya vid

[@SAMBADDU762]

Thanks for this estimation method

[@jasonmiller9738]

@tecmath Starting around the 6:49 mark you made two math errors. Other than that it's another great video.

[@johnryder1713]

This is about rounding up but theres nothing round about the brilliance of this channel

[@mj-lc9db]

Atleast he's trying! What have u done?!?

[@johnryder1713]

@@mj-lc9db D'uh, I love this channel what did you think I meant?

[@abiodunaghedo550]

Ur comment sounds like an insult.

[@johnryder1713]

@@abiodunaghedo550 I've no idea how it would be, Josh is the greatest

[@ariteg]

That's not an easy trick actually

[@SAMBADDU762]

Wow this trick is super amazing

[@TheHdawson]

On the second example above if you subtract 24 from 408 is 384- How did you get 380. The answer is correct, but, you lost me with the 380. How did you subtract 24 from 408 and get 380?? Shouldn't this number be 384????

[@anshumansharma7216]

Can you please explain why this works?

[@michaelempeigne3519]

Let's call x the base, k the scale factor and a and b the differences. ( kx +a) ( x + b ) = kx^2 + kbx + ax + ab = ( kx + kb + a )*x + ab

[@ekfilis]

47 x 408 explanation is wrong 408 - 24 is not 380

[@DavidHarrison-f2s]

You messed up the last one

[@ASPIRANT-zk5bh]

Sir, how to solve 73* 29 by this method?

[@tecmath]

I'd go 20 x 80. Go from there.

[@IS-py3dk]

@@tecmath 2:52 Sir here 307 rounds to 310 as the closest ten Why didu choose 300 ? 🤔

[@quinnkempert2422]

@@IS-py3dk that’s because 50 doesn’t fit into 310 very clean compared to 300

[@michaelempeigne3519]

Me too. @tecmath

[@sharonturner9466]

I can have the answer worked out by the time I do all of that. No use even doing it that way.🤔

[@m3nny125]

This is for mentally calculating them. you arent gonna do the standard multiplication method in your head. this is much easier to keep track of

[@yuriyvasechko4090]

-24+408=384 Cool method

[@TheHdawson]

Does anyone else see this error. How is he getting 380 when it should be 384???

[@greekgaddafi4468]

380*50=19000 384*50=19200 still correct answer but the process had errors oh well thanx for the genius methods though

[@IsThatYouShrek]

408 - 24 = 380...🤔🧐

[@joseguadalupereyes1809]

👍

[@ahmed85579]

Nothing understand 😐😐😐😐😐😐😐😐😐😐😐😐 sir

[@mikepeterson4746]

Easier to use your phone.

[@chimom5635]

😆😁👍