Subtraction in Seconds Best Tricks 2023

Subtraction in Seconds

Introduction

Subtraction in Seconds For most of us the name given to this chapter will not sound awesome. You may think that the name of this chapter should have been ‘Subtraction is Troublesome’. Subtraction is merely the other side of the coin of addition. Let me first address your concern. Why do we find subtraction to be a boring topic? I do hope the given example will tell you the actual truth behind our genuine fear.

Example:- Subtract 4768 from 8436

Solution:-

   8 4 3 6

– 4 7 6 8

__________ 

  3 6 6 8

The above example is an eye-opener for all of us. So many operations performed to get a simple answer may sometimes in annoy us and deter us from doing subtraction in Seconds our heads.

Why Is Subtraction in Seconds Tough to Handle?

There are probably two reasons for this.

1. a) While many of us learned our addition tables by heart     in school, few of us really mastered the conversion of these into subtraction tables with anything approaching the same thoroughness.
   1. b) Borrowing is regarded to be the main problem as far as subtraction is concerned. The traditional method of borrowing is tricky and many of us find ourselves forgetting to borrow, or borrowing twice.

   I shall try to address both of your concerns in this chapter and I will prove that once you complete this chapter you will say- hurray, subtraction is so easy!

   Mathematical Terms in Subtraction in Seconds

        9278     Minuend

      – 3041      Subtrahend

   _______________________

      6237 Remainder

   
   Complement method

   We shall now use the complement method to do subtraction in Seconds which will become an easy addition. The complement of a number is the difference of that number from base 10. I have placed two hands together to show you the complement of each number which you can use initially to understand the modus operandi. This device can be used to teach students this new technique. This is so simple that even a grade 3 student will rejoice in doing subtraction in Seconds by this method. 

              

   Warm-up Round for Mental Subtraction in Seconds

   To subtract mentally, try and round off the number you are subtracting and then correct the answer.

   To subtract 9 subtract 10 which is quite easy and add 1.

   To subtract 8 subtract 10 and add 2.

   To subtract 7 subtract 10 and add 3, etc.

   Example:- 56 – 9 = ?

   Solution:- In order to avoid carry; take 10 from 56 in your head which is a simple act and then add 1.

   5610 = 46

   Example:- 64 – 7 = ?

   46 + 1 = 47

   Solution:- Take 10 from 64 in your head which is a simple act and then add 3.

   64 10 = 54

   54 + 3 = 57

   Example:- 84 – 39 = ?

   Solution:- First round of the number 39 into 40 and add 1 in order to adjust it. The whole operation can be done mentally.

   8440 = 44

   Example:- 567 – 87 = ?

   44 + 1 = 45

   Solution:- First round of the number 87 into 100 and add 13 in order to adjust it. The whole operation can be done mentally.

   567 – 100 = 467

   467 + 13 = 480

   Don’t worry, these are warm-up exercises, which show that you can do simple subtraction mentally by manipulating the question according to your own ease. Let me play another warm-up game before I put my focus on your actual trouble. Wait, the climax is still a mile away!

    

   Subtraction in Seconds from a Power of 10

   Start moving from right to left. Replace every zero from the left with a 9 and the last zero with a 10. The extreme left digit before zero will get reduced by 1. Now do the simple subtracting without worrying about mistakes.

   Example:- 10000 – 462 = 7

   Solution:- 100      will       999 10

                 -462       become   -462

                             ______________

                                     9538

   Example:- 40000 – 1172 = ?

   Solution:- 40000    will    399910

                – 1172  become  – 1172

                           _________________

                                      38828

   Here, the extreme left digit i.e. 4, will get diminished by 1, and all the zeros thereafter will change into 9, except the last one. The last zero on the extreme right will be changed to 10.

    

   Example:- 50000 – 27172 = ?

   Solution:-50000        will  499910

               – 27172  become -27172

                              ________________                                                             22828

   Here, the extreme left digit 5 will get diminished by 1, and all the zeros thereafter will change into 9, except the last one. The last zero on the extreme right will be changed to 10. The whole operation can now be done mentally in no time.

   Here Comes the Method Which You Were Awaiting Eagerly

   Warning        Warning         Warning

   Before I proceed further I would like to remind you one thing   

   which is very important to mention here that if you haven’t read the examples before and are directly jumping over to the new method STOP and GO BACK to the previous examples and see the operation and understand the method and come back. I hope you will not do any cheating this time and follow my advice wisely. You may ask me a question:

   How Will This Method Help You Do Subtraction Faster?

   

   This will enable you to work from left to right. Though initially you will find it uneasy to work with, but mind you this method works better from left to right as against the traditional method which works from right to left. This technique will help you tackle any borrowing. The most annoying part of subtraction in Seconds comes when you are asked to subtract a larger number from a smaller one-the process that causes so much confusion and error.

   How Does This Method Operate?

   • Start subtraction in Seconds from left to right.

   In case you have to subtract a larger number from a smaller number just take the complement of the larger number to be subtracted and add it to the smaller number. While doing so, reduce the previous digit of answer by 1.

    Example:- 34 – 27 = ?

     Solution:-                  3  4

                                –       2  7 

                                _____________

                                         0   7

     

   We first put 1 down as 3-2 = 1. Now move to the second digit from left. Here you are in a critical situation where you need

   the help of complement method.

   4-7 = 4 + complement of 7 = 4 + 3 because 7 > 4                     

   Since we used the complement for the second digit from left so 1 written at the first place will be reduced by 1.

   Example:- 534 – 287 = ?

   Solution:- 

                                       534

                                    –  287

                             ______________

                                         247            

   5-2=3 3-8 = 3 + 2 (Complement of 8) = 5 4-7 = 4 + 3 (Complement of 7)  = 7

   Every time we use the complement its previous digit gets reduced by 1. For 3 – 8; we reduce the previous digit 3 by 1 and write 2 in its place. For the next subtraction in Seconds 4 – 7; we reduce the previous digit 5 by 1 and write 4 at its place as shown above. Hence, 534 – 287 = 247

   Example:- 54386 – 32458 = ?

    

                           54386

    

                   –       32458                                                 ________________

                           21928

   4 -2 = 2 = 1 (since complement in the next digit is used so

   2 is finally reduced by 1; 2 – 1 = .1)

   3-4 = 3 + 6 (Complement of 4) = 9

   8-5 = 3 = 2 (since complement in the next digit is used so 3 is finally reduced by 1; 3 – 1 =2)

   6-8 = 6 + 2 (complement of 8) = 8

   I do hope these examples have given you some amount of confidence and you are in a position to enjoy subtraction in Seconds a little bit. By this time you must be finding it a little easier to work from left to right and cancelling tens in the answer rather than borrowing from the neighbouring number. Once you become fully used to it, you will find it far more natural and infinitely more.

   

   foolproof than the older system

   foolproof than the older system. It has been estimated that 90 per cent of all mistakes in subtraction in Seconds happen due to forgetting to borrow or borrowing too much. Since this method eliminates borrowing altogether, this method gives you accurate and faster

   result.

   Handling Slashed Zero (0)

   There is absolutely no need to worry when you get a slashed zero in between the operation. Reduce the value to the left by 1 which in turn will make slashed zero 9.

   204 – 9  = 194

   Example: 14567892 – 4567899 = ?

   Solution:-   1 4 5 6 7 892

                      -4 5 6 7 8 99

                                                                                ____________________

                                                                                     10.0.0.0.0.0.3

      ANS  =    9999993

   Nothing from 1 = 1. Put down 1.

   4 from 4 = 0. Put down o

   5 from 5 = 0. Put down 0 and so on, you get o until you come to the final column.

   In the final column, 9 >2, hence 2-9 = 2 + 1 (complement of 9) = 3. Put down 3. As discussed earlier, whenever you use

   

   complement for subtraction in Seconds,

   complement for subtraction in Seconds, cancel a 10 by slashing the digit on the left. The digit to the left is 0. Slash it. Whenever you slash a 0, you must go back and slash the digit to the left of it too. The next digit is also a 0, so you have to keep on slashing until you slash a digit that is not zero, and here you find the first digit from the left which is not a zero, so this too will be slashed by making 1 into 0 and all other 0s into 9.

   Example:- 4573289 – 258684 = ?                                                     

   Solution:-               4573289

                              –  258684

                       _______________

                                4314605

   Here,

   4 – nothing = 4

   5-2=3

   7-5=2=1 (complement is used in next operation so this digit is 1 after slashing)

   3-8=3+2 (Complement of 8) = 5= 4 (complement in next operation)

   2-6=2+4 (Complement of 6) = 6

   8-8=0

   9-4=5

   Before I ask you about your opinion about the method discussed let me put few examples for you to practise and get a command over the method.

   1. a) 12345        b)     86406

             -4567                 -37606

    _______________  ________________

   1. c) 9000045       d) 88888888 

            -7865745           -24569997

   _________________ ________________

   So, what is your view on the above method of subtraction in Seconds? Isn’t it cool?

   This is flawless and quicker than the traditional method and with a little practice you can do most of the operations in your mind without using pen and pad and can proudly say  subtraction in Seconds IS FUN.