have you ever seen those videos on the internet in which students are using their fingers to solve long addition and subtraction problems extremely fast so till the end of this video you will also be able to solve these kinds of long addition and subtraction problems by just using your fingers as an abacus or in other words let's learn kung fu mathematics [Music] so hello geniuses welcome to this another video of method genius mental math series so before starting this video let me tell you about the sponsors of this video named speedwrite this is a really cool tool with which you can save yourself from the assignment deadlines these days students get lots and lots of assignments and sometimes the deadline is so close that we don't have time to write an assignment here speed write can help let's take a simple example let's say i have to write an assignment on sun but i can just copy and paste it from wikipedia so what i can do is this i can copy this to speed write and there speedwrite uses an ai to rewrite the text given to it in a completely unique way and every time you do it it will generate a completely new text so if wisely used this tool can help you save a lot of your time which you can use to do something better than those useless than redundant assignments so now let's come back to kung fu mathematics why i call it kung fu mathematics is because the students doing it looks like they are doing kung fu but originally this method is known as cheese and pope and the book that i am using to teach you this method is the complete book of chison bob by young pi it uses our fingers in a really efficient way and with which we can do phenomenally fast calculations because in this method our brain rests our brain has only one job and that is to count nothing else in other methods like in left to right and other methods we always needed to keep track of the answer we needed to use our memory our brain was stressing a lot but in this method our brain is mostly relaxed and our fingers are doing most of the work so the most crucial part of this method is being able to represent numbers on your hands and the faster you can switch from one number to another number and there are some rules the faster you can apply those rules the faster you will calculate so this one will take a little bit of practice but after practicing you can do phenomenally fast calculation really is the end it is not that tough so now at first let's learn how to represent numbers from 1 to 99 on your hands our right hand represents numbers from 1 to 9 it is like this so this is 1 this is 2 this is 3 this is 4 simple but now this is not 5 this is 5 okay this is 5 and this is 6 this is 7 this is 8 and this is 9 so from 1 to 9 in here and this is 10 20 30 40 and this is 50 60 70 80 and 90. now we have the representation now we can represent any number from 1 to 99 on our hands so let's take an example let us represent 12 on our hand so see this is 10 and we need 2 this is 12 now let us represent 28 so 20 and 5 6 7 8 this is 28 so now try representing 36 on your hand so this is 10 20 30 and 6 5 and 6 so this is 36 now this looks pretty simple how simple is this but this is really really powerful now try to represent these numbers quickly on your hand as fast as you can switch from one number to another number now what you have learned is the essence of chase and bob or kung fu mathematics now with this you can do any addition problem whose answer is less than 99 on your hands using cheese and bob so let us take an example we need to add 73 and 25 now firstly you can also use left to right method and this is a really easy problem if you have seen my previous all videos there are tons of ways you can do it but now we will use our fingers to do it so first represent 73 how 50 60 70 now 373 now represent 25 so we have 20 in here so 10 20 20 and 5 5 so what is this this whole is 90 and this is 5 6 7 8 98 is our answer so right now i was explaining this but in reality if you do it you just need to hear someone saying like 70 3 and add 25 and at the end count this is 90 this is 5 6 7 8 so 98 so in here our mind is resting you can see it by using the left to right method there our mind is doing all the work but in here our hands are doing the most of work that's why the students are able to add long strings of numbers because every time they add it they don't need to keep track of the answer their hands have the answer and in that answer they're adding further and then further and by doing this they are doing that fast calculation so now there is a little limitation in our hands the previous question that i have taken is specially designed not to include that limitation but let us take this question 32 plus 28 so let's first represent 32 so here's 30 and 2 32 now we need to add 28 to it now how would we do it see in here i have just 10. so there is no 20 in here then what would i do in here you need to be creative with cheese and bob by practice this will come automatic so in here we need to add 20 we don't have fingers for 20. what can we do is this we can add 50 and subtract 30 so we have 50 so c30 plus 20 is basically 50 now 28 for it we also don't have fingers so what we can do is this we can add 10 and subtract 2. so what we have in here 50 60 60 is our answer so in chisholm because we have only 10 fingers we have this limitation which we can overcome by knowing these simple rules these are like really simple rules like you don't need to memorize them for example let's say you have this finger opened already and now you want to represent 9 in here how would you do it it's simple using this equation add 10 and subtract one the only thing that you need is the practice on your hands to do it even faster now let's take a subtraction problem with cheese and pop 54 minus 32 try to do it yourself how would we do this see 54. okay 54 minus 32 now in here what we have this we need to subtract 30 first so what we can do is this we can first subtract 50 and then add 20 so this should be very quick 20 and 2 we need to subtract 2 but we have in here 22 so this is how easy cheese and bob is so in reality this should be this quick like someone saying to you you need to do this he's saying 50 4 minus he said minus 10 like prepare your brain that he's saying minus and he said 30 and quickly 30 and 2 we need to like subtract 2 not open it like subtraction is closing it so what we have then 22 say it quickly so like you have not taken any time to solve this problem your hands only just solved your problem so this is basically the real power of jason bob okay so now let's try this long addition problem like someone telling you 15 plus 12 plus 8 plus 29 and so on how would you do it so do it with me first represent 15 so 15 now add 12 to it so 12 now in here this is the real thing if you are doing it otherwise you will need to keep track of the answer but now we don't need to keep track of the answer give us the next number in here so now add 19 so adding 10 and now for 9 we don't have fingers so what we can do is add 10 and subtract 1. now we have the answer in our hands we don't need to keep track give us the next number now add 29 for adding 20 we can add 50 and subtract 30 and add 9 so adding 10 and subtracting 1 so we have the answer in here give us the next number so add 11 10 11 now add 8 in here so if we're adding 8 we will add 10 and subtract 2. we can't subtract 2 in here because like we don't have two fingers up so what we can do is this we can subtract 5 and then add 3 so what do we have in here we have 90 and 4 so 94 is our answer so this is how we use this and bob to do those addition kinds of problems now what you have learned is almost all the cheese and bob that you need to know now the only thing you need to go beyond 100 is the representation of hundred so it is pretty simple see this is 10 20 30 40 50 60 70 80 90. 90 and this is 91 92 93 94 95 96 97 98.99 so we have 99. now if you want to represent 100 then what do we do is this like we close everything like we are going the next level so closing everything and use your right hand because it was in 99 now if you like hold your hand like this now this is representing 100 and your this this finger should be like this so this is 400 now how you read it you first read write then read left and then read right so this is basically 100 this is zero and this is also zero because no other finger is open so this is representing 100 now this this is representing 200 this like half open this is representing 300 400 now 500 600 700 800 and 900 so this is basically the same thing just half open fingers and hand like this represent that you are in hundreds okay now try representing 153 on your hands so now let's represent 153 so this is 100 and this is 50 now representing three so now for representing three this finger is representing hundred we also need to represent one with it what do we do we half open it and then full open the other two fingers so this is representing basically like this this is hundred fifty and this three because this now half open this is not like this this is like this so now you can see as we are going further our hands are getting a little bit messier and this is why i will teach you to only count till 999 because after that our hands get a lot load messier and mathematics goes somewhere like this and it is only kung fu which is left so we will count till 999 now let's do a simple addition problem with this method so add 68 and 49 with cheese and bob so first let's represent 68 so 50 60 and 5678 68 now we need to add 40 into it how would we do it because we have just three fingers left in here so what we can do is this we can add 100 and like close this half a hundred and then we can subtract 60 so we have added 40 now we need to add a 9 for adding 9 we can like add our 10 and subtract 1 like subtracting 1 and this finger like half open so what we have in here see 100 this is representing 10 and this is 5 6 7 so how much 117 is our answer so this is how basically we can do problems beyond 100 using json bob so now finally try representing these numbers on your hands as swiftly as you can and if you can do it i have a challenge for you you can try doing this problem add 482 and 394 using cheese and fob and if you can do it then congratulations you are a master at jason pope so just a fact in reality we can represent efficiently numbers till 9999 on our hands this is the power of cheese and bob but i'm not teaching it because this was already messier and that is more more messier but if you want to learn it you can learn it from this book and as i always say you need to practice it and if you watch my previous video i have said it many times for practicing i have made a game known as math blob run in which there is a good blob and bad blob the bad blow wants to eat our good blob but solving mental math questions will save your blob so you can use that game to practice cheese and bob too and also do not forget to join us on our discord server there we are making a really good maths community and finally thanks for watching this video i hope you have enjoyed and always remember that math is everything