Vedic Math - Base Multiplication

Note: Vedic Math Blog has been moved to http://vedicmath.vedantatree.com/. Please bookmark the new address for new and existing blogs.

Today, we are going to learn the GENERAL formula of multiplication. This is simple and easy technique and good part is that it is applied to almost all the cases. This method works better when numbers are near their base value. After going through the below discussed method, you will see that multiplication tables are not required for calculation above 5 x 5. You will be able to do all types of multiplication involving bigger multiplicands and multipliers quickly and easily; like for '789789 × 999997'. All the sutras (formulae) of Vedic Math are short and simple; and with the practice of the techniques, most of the calculations become a playful experience for you.

Following is the sutra that we will follow today:

The formulae (sutras) are : “All from 9 and the last from 10” and "Vertically and Crosswise"
The algebraical expression is :(x+a) (x+b) = x (x+a+b) + ab.

From the title of the article, you can understand that today we shall do the multiplication by taking the base of numbers. So, first we need to be familiar what is 'base'. The term ‘base’ in Vedic Math has a broader meaning than you may be used to. We work in a base 10 number system, but within Vedic Math the ‘base’ is the number you will use as a basis for calculation. The numbers taken can be either less or more than the base considered. The difference between the number and the base is termed as deviation. Deviation may be positive or negative.

Now observe the following table.

Number      Base         Number – Base       Deviation
   13             10                  13 - 10                      3

    7              10                     7 - 10                    -3

   89             100                  89 - 100                -11

 1110           1000             1110 - 1000              110

99998          100000       99998 - 100000            -2

So, the deviation obtained are from "All from 9 and the last from 10" sutra (formula).

Following are the cases which we shall discuss here:
A. Numbers are below the base number
B. Numbers are above the base number
C. One number is above the base and the other number is below it
D. Numbers are not near the base number, but are near a multiple of the base number, like 20, 30, 50 , 250 , 600 etc
E. Numbers near different bases like multiplier is near to different base and multiplicand is near to different base

Let us discuss these cases one by one.

A. Numbers are below the base number

Working with Base 10
Let us take an easy and simple example to start this technique. Suppose we have to multiply 6 by 8.
Now the base is 10. Since it is near to both the numbers.
Place the two numbers 6 and 8 above and below on the lefthand side (as shown below). Subtract the base value (i.e. 10 in this case) from both of the numbers and write down the remainders (i.e. 4 and 2) on the right-hand side with their deviation sign (-).

6 x 8   

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Productivity, improvement in efficiency is quite a hot mantra nowadays to be successful and to achieve the growing number of goals. With the fast moving life, demanding expectations, people are in continuous pressure to improve what they are doing now, to manage multiple tasks simultaneously, and to remember many things which they need to complete in a day or probably in few days. Won't you feel, sometime our mind gets exhausted with this sea of information and tasks. However, to meet the expectations, we have to manage it. Managing information, planning ahead, scheduling, remembering the schedule and then execute it, is the key to success. But one point is certainly clear that we need some help to manage this bulk information and tasks etc. So how should we do that? Are we talking about having a personal secretary.. sort of :). But everyone can not afford to hire a personnel for this management. So.....

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Vedic Math - Mathematical magic trick

Note: Vedic Math Blog has been moved to http://vedicmath.vedantatree.com/. Please bookmark the new address for new and existing blogs.

Let us take a break from calculations and enjoy a small magical mathematics trick.

1. Think a number (any number). To keep it easy, think any number having 1 or 2 digit.
2. Now double this number i.e. multiple by 2.
3. Add 12 to the result
4. Divide the total by 2.
5. Subtract the original number from above result.
6. And you will always get '6' as final result.

Try this one with different numbers, and you will see that the sequence always produces the '6' as result ,no matter which number was originally selected.

For example, if the original number is 15.
1. 2 x 15 = 30
2. 30 + 12 = 42
3. 42 / 2 = 21
4. 21 - 15 = 6

You must be curious that how this magic trick is working. Following is the concept for this magic trick:

Let us take a number be x and the steps performed by us are:
1. 2x
2. 2x + 12
3.(2x + 12) / 2 = x + 6
4. x + 6 - x = 6

So, in last step, we see that whatever number we choose (as x) will finally result in '6' with above calculation. After knowing the formula, now you can change the answer by changing the formula. For example, if you want to change the answer to '4', then you add twice of that '4' i.e. '8' in the second step.

Enjoy this trick!!

Vedic Math - Multiplication of numbers whose last digits add to 10 and first digits are same and vice-versa.

Note: Vedic Math Blog has been moved to http://vedicmath.vedantatree.com/. Please bookmark the new address for new and existing blogs.

We had discussed this method in our previous articles for 2-digit numbers and today we shall explain the same method for 3-digit numbers.

A. Numbers whose last digits add to 10 and the remaining first digits are the same
Case 1: When sum of last two digits number is 100 
Example: 392 x 308
Here we can see that right digits sum is 100 i.e.(92 + 8) and left side digits are same. Here we can now apply the same method, which we discussed earlier for 2-digit number. But this time we must expect to have four figures on the right-hand side.

• First, multiply the right side numbers(92 x 08) and the result is 0736.
• Second, multiply 3 by the number that follows it, i.e.4, so the result of (3 x 4) is 12.
• And now the final output is 120736.

Example: 795 x 705
Here 95 + 05 = 100 and left side digits are same i.e. '7'. Hence it qualifies for this case.
In calculation, we shall multiple the last two digits and the left digit i.e. '7; with its next number '8'. So the calculation is:
795 x 705 = 7 x 8 | 95 x 05
                 = 56 | 0475
                 = 560475

Example: 866 X 834
Here 66 + 34 = 100 and left side digit is 8 and its next number is 9. So the calculation is:
848 x 852 = 8 x 9 | 66 x 34            (Note: For 66 x 34, we shall discuss in our upcoming articles)
                 = 72 | 2244
                 = 722244
         
         
Case 2: When sum of whose last digits is 10  and the remaining first digits are the same   
Example: 241 x 249
Here we can see that right digits sum is 10 i.e.(9 + 1) and left side digits are same i.e. 24. So we can now apply the same method as described above.
241 x 249 = 24 x 25 | 1 x 9
                 = 0600 | 09
                 = 60009

Vedic Math - Multiplication of numbers with a series of 1's

Note: Vedic Math Blog has been moved to http://vedicmath.vedantatree.com/. Please bookmark the new address for new and existing blogs.

In the previous article, we learnt the technique of "how to multiply numbers with a series of 9’s". In this article, we shall learn the technique of "how to multiply numbers with a series of 1’s". So, we shall multiply the numbers with 1, 11, 111,..... etc.

I. Let us start with the vedic multiplication by 11

In this technique, we use "vertically and crosswise" vedic sutra. Take example of ab x uv, and apply the sutra as follows:

       a         b
       u         v
   ---------------------
   a x u | av + ub | b x v
   ---------------------

(Here '|'  is used just as separator)

Here we are splitting the answer in three parts as following:

• vertically                         =(b x v)
• crosswise multiplication and add   =(a x v) + (b x u)
• vertically                         =(a x u)

During multplication with 11, u=1 and v=1, means:

           a               b
           1               1
         --------------------
           a  |  a + b  |  b
         --------------------


Example:  Multiply 53 by 11

Vedic Math - Multiplication of numbers with a series of 9’s

Note: Vedic Math Blog has been moved to http://vedicmath.vedantatree.com/. Please bookmark the new address for new and existing blogs.

Another special case of multiplication is, multiplication with numbers like 9, or 99, or 999, or 9999.....so on. It feels like if multiplier is a big number, the calculation will be tough. But, with the help of vedic math formulae, the multiplication is much easier for all '9' digits multiplier. By using the method given below, we can multiply any number with 99,999,9999, etc. very quickly.

Please note that the methods or the vedic formulae, that we use in this calculation, are "By one less than the one before"  and "All from 9 and the last from 10".

There are three cases for the multiplication of numbers with a series of 9's.

• Case 1: Multiplying a number with a multiplier having equal number of 9’s digits                                              (like 587 x 999)
• Case 2: Multiplying a number with a multiplier having more number of 9’s digits                                             (like 4678 x 999999)
• Case 3: Multiplying a number with a multiplier having lesser number of 9’s digits                                             (like 1628 x 99)

The method to solve 'Case 1' and 'Case 2' is the same, but for 'Case 3', the method is different. Let us start with 'Case 1'.

Case 1: Multiplying a number with a multiplier having equal number of 9’s digits

Multiply 587 by 999

           587
       x  999
       ------------
        586 413
       
Solution is,

•  Let us first do the calculation by conventional method to understand the solution. Result will be 586413.
• Split the answer in two parts i.e. '586' and '413'.
• Let's see the first part of the result, i.e. 586. It is reduced by 1 from the number being multiplied i.e. 587 - 1 = 586. {Vedic sutra "By one less than the one before"}
• Now see the last part, i.e. 413. Subtract the multiplicand i.e. 587 from 1000 (multiplier + 1). Vedic Sutra applied here is "All from 9 and the last from 10", and hence we substract 587 from 1000. So the outcome will be (9 -5 = 4, 9 - 8 = 1, 10 - 7 = 3) , and result is 413. Refer to image below for more clarity:

Vedic Math - Squaring of numbers near '50'

Note: Vedic Math Blog has been moved to http://vedicmath.vedantatree.com/. Please bookmark the new address for new and existing blogs.

In this article, we pick another special case of squaring i.e. squaring numbers which are near 50. It can have two cases, which are:

• Case 1: Numbers greater than 50.
• Case 2: Numbers lesser than 50

In both the cases, we need to take 50 as the base value. First let us take 'Case 1' i.e. 'Numbers greater than 50'.

Case 1 -
Take an example: Say, 54²=2916 
Consider this answer in two parts: 29 (first part) and 16(second part). Now let us study, how Vedic Math can help us to achieve this answers or both of these parts.

As we are taking '50' as base, so the number presentation will be like 50 + 4. So the first part is 50, and second part is 4.

For the first part of the answer:

1. Pick the first part i.e. 50.
2. Pick the first digit i.e. 5
3. Square this digit i.e. 5² > 25
4. Add 4(second part) to it
5. And we get our first part of the answer i.e. 29 (25 + 4).

For the second part of answer, following are the steps:

1. Pick second part i.e. 4
2. Square this digit i.e. 4² > 16
3. And we get our second part of the answer i.e. 16

So the answer is 2916

Let us understand it with another example to make it more clear. Say, 61²=3721
As we are taking '50' as base, so the number presentation will be like 50 + 11. So the first part is 50, and second part is 11.

For the first part of the answer:

1. Pick the first part i.e. 50.
2. Pick the first digit i.e. 5
3. Square this digit i.e. 5² > 25
4. Add 11(second part) to it
5. And we get our first part i.e. 36 (25 + 11).

For the second part of answer, following are the steps:

1. Pick second part i.e. 11
2. Square this digit i.e. 11² > 121
3. Now the result is of three digit. So the first digit (1) will be added to the first part i.e. 1 + 36 = 37
4. So first part becomes 37 now
5. And second part of answer will be 21 

So the answer is 3721. Refer to image below for visual representation.

Vedic Math - Squaring Of Numbers Ending with '5'

Note: Vedic Math Blog has been moved to http://vedicmath.vedantatree.com/. Please bookmark the new address for new and existing blogs.

In this article, we shall discuss a very common and interesting trick to square those numbers quickly which are having '5' as last digit. For example, what is the result of 65², 85², 125² ?

Let us start with an example:- 35 x 35. How will you multiply?

The conventional approach is-

     35
   x 35
   -------
    175
   105
 --------
   1225
 --------
 In above problem, we followed the following steps:

1. In first step, we multiply 5 by 35, get 175 and wrote it below the line.
2. In second step, we multiply 3 by 35, get 105, wrote it below the first step and leave one space from right.
3. In last, we add results from both the steps and get 1225 as answer.

Now here is the magical trick or quicker way to do this calculation using Vedic Math (to square any number with a 5 on the end). Let us have a look on the same example once again, following 'Vedic Math' steps to solve it.

1. In 35, the last digit is 5 and other number is 3.
2. Add 1 to the top left digit 3 to make it 4 (i.e. 3+1=4) (See the image below).
3. Then multiply original number '3' with increased number i.e. '4'. Like 3 x 4, and we get 12.
4. Now you can see that this is the left hand side of the answer.
5. Next, we multiply the last digits, i.e 5 x 5 and write down 25 to the right of 12.
6. And here we come up with a desired answer, 1225
7. Visual representation is given below.

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• Apache JMeter - Free and Open Source
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