A small start..

There are many contents in this Solving process. Basics are 'Simplifications'. In those Additions, Subtractions, multiplications and divisions take a key role. Additions and subtractions are tough for us.. in these 5-digit calculations are also very easy. Now, coming to multiplications and divisions, first of all u need to know tables very thoroughly. In these, 2 or 3 digit calculations are also tough. So now, we will see how to multiply 2-digit numbers.
 The Rule is " | X | "
  a     b
  |  X  |
  c     d
ie the answer will be of min. 3-digit number. so UNITS digit will be " | "  =  b*d or bd
                                                                       TENS digit will be  " X " = ad + bc
                                                                 Hundreds digit  will be  " | "  = ac
Sample
2   3               5     6
| X |                |  X  |
2   1               4     2      here 6 x 2 = 12, 5x4 = 20, ans 5x2 + 6x4 =  10 + 24 =34
4 8 3             20 12
                    + 34
                     2352


The above mentioned is the basic formula for any type of 2-digit multiplication


To know squares

(a+b)^2 = a^2 + 2ab + b^2

You know this formula right.. the same way 
to get square of a number UNITS digit will be --- b^2
                                        TENS digit will be --- 2ab
                               HUNDREDS digit will be -- a^2


34^2 =   9 4 6
       +    2 1                3x3 =9, 4x4 = 16 and 1 is carried to tens digit
       =  12 5 6              2x3x4 = 24, where 2 is carried to next digit





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