Cool math mental multiplication trick - become a genius solving math instantly - By tecmath
Transcript
| 00:0-1 | Good day and welcome to Tech Mouth Channel . What | |
| 00:02 | are we Having a look at this video today is | |
| 00:03 | just a peculiar little maths trick for multiplication . It's | |
| 00:07 | a it's a really good little one , so I'm | |
| 00:09 | just gonna see if you can figure it out . | |
| 00:11 | Um I will obviously give you the secret with this | |
| 00:15 | , but it's a really good one for working out | |
| 00:17 | numbers instantly , like , of uh multiple digits are | |
| 00:20 | working at this multiplication , so I'll give you an | |
| 00:22 | example . Uh What about this one here ? I'll | |
| 00:25 | get you a workout cf fast . You can work | |
| 00:27 | out 59 times 51 . Um Look , I reckon | |
| 00:30 | you should actually be able to work at it instantly | |
| 00:32 | . The answer to that is 3000 and nine . | |
| 00:36 | Okay . Uh did you see how I worked that | |
| 00:40 | out ? Maybe maybe that owns a little bit too | |
| 00:42 | hard for you . What about ? I'll give you | |
| 00:44 | a different one . We'll give you how we do | |
| 00:47 | this by the way . So don't get too upset | |
| 00:49 | by this . What about 42 times 48 . Can | |
| 00:54 | you automatically work out the answer to that ? Did | |
| 00:57 | you get the answer of 2016 ? You might say | |
| 01:03 | , how am I doing this ? What's the secret | |
| 01:05 | now look , this is a it's a fairly limited | |
| 01:09 | little trick , but it's it's a good little trick | |
| 01:10 | nonetheless , and I'll show you how this works . | |
| 01:13 | First off , you're going to notice a couple of | |
| 01:15 | things about these numbers , and these two conditions are | |
| 01:17 | critical for doing this particular little maths trick . First | |
| 01:20 | off , you don't notice that these two numbers that | |
| 01:23 | are multiplying the start of them is the same . | |
| 01:26 | You notice that the other thing you might notice is | |
| 01:29 | this These two numbers here add up to 10 . | |
| 01:32 | Now , these two conditions have to be met for | |
| 01:34 | this mouth stricter work . Okay , So I'll show | |
| 01:37 | you how you use this to actually work out the | |
| 01:40 | answer . Okay ? So as I said , it's | |
| 01:43 | it's a fairly limited treatment . It's a good one | |
| 01:45 | . Anyway , so first off what we're doing , | |
| 01:48 | we're doing this this particular trick is we look at | |
| 01:50 | the number here in front of that . We look | |
| 01:52 | at these two numbers and we go one number above | |
| 01:54 | it . So the number above four is five . | |
| 01:57 | And then we multiply these two numbers to get our | |
| 02:00 | first digits . All right , so five times four | |
| 02:03 | he's 20 . Then with our last two numbers to | |
| 02:07 | get our last two digits . What we do is | |
| 02:09 | we multiply these two numbers . Okay . Two times | |
| 02:12 | 8 . 16 . Yeah . Pretty cool . Yeah | |
| 02:15 | . What about I'll give you another one of these | |
| 02:20 | . So What about we do this particular one ? | |
| 02:23 | What about we do uh 63 times 67 . So | |
| 02:30 | , can you automatically get the answer to this ? | |
| 02:33 | Okay , Number above this is 77 Sixes are 42 | |
| 02:37 | And seven threes , or 21 . That's a really | |
| 02:41 | , really cool mastery . You do this on people | |
| 02:43 | think you're offending ingenious ? You don't even need to | |
| 02:45 | hesitate . Okay . You do need to set it | |
| 02:48 | up a little bit though , don't you ? So | |
| 02:50 | what about we'll give you a bunch of these , | |
| 02:51 | see how you go with them and we'll answer the | |
| 02:53 | questions , okay ? We'll go through them . So | |
| 02:56 | what about we do this one ? Um What about | |
| 02:59 | 105 ? Actually going to change 100 and five and | |
| 03:04 | I want to do that one because 205 times 100 | |
| 03:07 | and 5 to 104 times 100 and six . Okay | |
| 03:12 | . What about we do 31 times 39 . And | |
| 03:19 | we do uh 62 times 68 . So I don't | |
| 03:26 | reckon you need to pause the video to work this | |
| 03:29 | out . Let's work them out on the spot . | |
| 03:30 | Next number above 10 is 11 . 11 by 10 | |
| 03:33 | is 100 and 10 6 . Fours 24 . Okay | |
| 03:39 | number but this is 443 to 12 and then we | |
| 03:43 | have one times nine which is nine . And we | |
| 03:45 | write this as oh nine because it's the last two | |
| 03:47 | digits . Then we go this 16 Sixes are not | |
| 03:51 | 66 is 67 of 42 . Almost fell for that | |
| 03:54 | myself . And then we have to H . R | |
| 03:57 | . 16 . Pretty cool . I now you can | |
| 04:00 | incorporate this with a few of the other maths tricks | |
| 04:02 | which I got on the videos and you can even | |
| 04:04 | start getting a few really really crazy sorts of things | |
| 04:07 | you can apparently work out . Yeah and I'll give | |
| 04:09 | you an example of this so I'll give you the | |
| 04:11 | really , really hard won um Say we do something | |
| 04:14 | like I think we should do this 176 times 174 | |
| 04:23 | . Now , if you've done a couple of my | |
| 04:25 | other videos , I put the link up by the | |
| 04:27 | way , right now , you can work out this | |
| 04:29 | next number above , which is We're going to do | |
| 04:32 | 18 x 17 , so 18 times 17 . The | |
| 04:38 | answer to that is 300 it seeks . Okay , | |
| 04:43 | there is a little trick by the way , for | |
| 04:45 | working these out And there we go . 6424 . | |
| 04:50 | Okay , the link for how to work out 18 | |
| 04:52 | x 17 , instantly , by the way , yes | |
| 04:54 | , I will put the link up as I've said | |
| 04:56 | , all right , do you want that trick obviously | |
| 04:59 | has a fair degree of limitation , but I think | |
| 05:01 | it's a it's just a really interesting little maths tricks | |
| 05:04 | . So I thought I'd put it up because that's | |
| 05:05 | what this channel has pretty much becoming all about anyway | |
| 05:09 | . I hope you like that , See you next | |
| 05:10 | time . |
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