Mutiplication by 99

We can multiply any number with 99 using following Vedic mathematics Techniques.

Consider one example 987678 x 99
    1. Subtract one from multiplicand
       i.e. 987677
    
   2. First Group the multiplicand 2 digit each from unit digit place
         i.e.      98  76  77

   3. Write Same group below the first group leaving one group from the left
         i.e.      98    76    77
                            98    76    77
   4. Extreme right group subtract from 99 and remaining part just sutract
       i.e.       98     76     77
                            98     76   77
                 ____________________
                   97    78      01    22
                _____________________

   5. Final Answer is = 97780122