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The table shows the positional weight of decimal number (724) .
                                                                                  10


                                                     Hundreds                   Ten                   Units



                  Weights                                 10 2                   10 1                   10 0

                  Real Value of each digit              7 × 10 2               2 × 10 1               4 × 10 0

                  Result                                 700                     20                      4



                 For Example: (3698)  10
                                 0
                 8 signifies 8 x 10 = 8
                                  1
                 9 signifies 9 x 10 = 90
                                  2
                 6 signifies 6 x 10 = 600
                 3 signifies 3 x 10 = 3000
                                 3
                 Upon adding them = 3000 + 600 + 90 + 8 = 3698


                 BINARY NUMBER SYSTEM
                 A number system made up of only two digits: 0 and 1, is known as the binary number system.

                 When the binary number system is used, every number is formed using only 0 and 1. The word
                 ‘binary’ comes from ‘Bi’ meaning two that’s why the base of the binary number is 2. It is also
                 known as the base-2 system.


                 Formation of Binary numbers
                 As you know the binary number system consists of two digits: 0 and 1 and its base is 2. Each
                 digit or bit in a binary number system can be 0 or 1. A combination of binary digits may be
                 used to represent different quantities like 1001. The positional value of each digit in a binary

                 number is twice the place value or face value of the digit on its right side. The weight of each
                 position is a power of 2. The place value of the digits according to position and weight is as
                 follows:


                    Position         3           2            1          0                       –1          –2
                                                                                      •
                    Weights          2 3         2 2         2 1         2 0                     2 –1        2 –2



                 For example: 10101 or (10101)  is
                                               2
                                                   1
                       4
                                 3
                                                           0
                                         2
                 = (1 x 2 ) + (0x 2 ) + (1x 2 ) + (0x 2 ) + (1x 2 )
                 = (1 x 16) + (0 x 8) + (1 x 4) + (0 x 2) + (1 x 1)
                 = (21) 10

                                                                                                  Number System    9
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