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# Vertically and Crosswise – A simple and effective method of multiplication

In my workshops I have seen kids and children struggling with multiplication . Specially if it is two or three digit multiplication their faces will just turn sad in few seconds. And they will shout in unison , ” No Mam not again ”

So I teach them a simple method of multiplication which is not only easy to remember  but saves a lot of time . Once you understand this method , the time taken to do two digit and three digit multiplication reduces by half.

These methods are derived from Atharv Veda and they make calculations really simple.

This method is called Vertically and Crosswise

Two digit multiplication

We are multiplying here 12 and 34 Step 1

Multiply the digits at unit place . Here they are 2 and 4 . Since it is 8 you keep the digit at units place . If in a case you get two digits you carry the ten’s digit to the next place value . This step is called vertically

Step 2

Multiply the digits at unit’s place to the  digit at tenth place and add both of them . Keep the unit’s digit and carry the remaining digits at the next place value. . This step is crosswise . When we multiply here in the above case i.e 1 with 4 and 2 with 3 , we got 4 and 6. When we add we got 10 . We kept 0 and carried 1 to the next place value

Step 3

Multiply the digits at the tenth place . Add the digits to the carry over digits. This step is again called vertically . We multiplied 1 with 3 here and added the carry over 1 from step 2.

Multiplication of three digit number by three digit number

Diagramatic representation of multiplication of 3 digit number by 3 digit 1   2   3

4   5   6

_________________

4   3    8    7      8

1   2   2    1      +

___________________

5    6    0    8     8

Let us work another problem by placing the carried over digits under the first row and proceed.
Steps:
i) 3 X 6 = 18 : 8 is kept at the unit’s place and 1 is carried over to the next place value.

ii) (2 X 6) + (5 x 3) = 12 + 15 = 27 ; 7, the carried over digit 2 is placed to the next place value

iii) (1 X 6) + (3 X 4) + (2 X 5) = 6 + 12 + 10 = 28 ; 2, the carried over digit is placed below fourth digit.

iv) (5 X 1) + ( 2 X 4) = 5 + 8 = 13; 1, the carried over digit is placed below fifth digit.

v) ( 1 X 4 ) = 4

vi) Respective digits are added with the carry over digits.  So the answer is 56088

This method can be applied for any two digit or three digit multiplication and it reduces the time by half .

Keep watching this space for some more easy tricks which makes calculation really simple.