VADIC MATHS - LESSON NUMBER TWO.

after learning how to square a number ending with 5 now we will do something called comman base method.

this method is a technique of multiplying number which comes under same base.
this base could be anything like
-10
-100
-1000 etc.

to multiply two numbers we just need to make them subtracted or added to a comman base.
lets do an example.
MULTIPLY 99 X 92

step 1:-MAKE COMMAN BASE
here the base is 100. (coz while setting the base we should keep in mind that the base should be closest to the numbers to make sure that the minimum calcultaions will be required.

step 2:-SUBTRACT THE NUMBERS FROM THE BASE AND WRITE THEM IN THE ORDER.

100- 99 = 01
100- 92 = 08
(we write the number we get after subtraction in as many digits as many zeros we have in the base, here we have 2 zeros in 100)
AND YOU HAVE TO WRITE THESE IN THE FOLLOWING SEQUENCE

99 01
X !
92 08
----------
91 08 = 9108 is the answer


this 91 we get my subtracting (92-01) or (99-08) cross digits
and 08 we get by multipling the straight line of the digits we get after subtraction from base (01 X 08)
the zero wil remain coz we have two digits in our base.

isnt it simple

now lets try this with two digits which
one is bigger than base another is smaller than base

112 X 92

so step 1:-
112-100 = +12 (no need to add zero coz we have only two zeros in base and we have two digits in 12 as well)
92-100 = -08 (the sign will be on negative coz 92 is lesser than 100)

(in the previous example we ignore negative sign by subtracting both the digits from 100 but in this case its not possible)

so now we have

112 +12
92 -08
-------------
104 -96

now we have to right it like this

10400
- 96
-----------
10304 thats the answer
-----------

you can try this on any number

try it

tables are still important

learn from 1X30 to 30X30

we will keep posting more tricks till then master these ones

gaurav