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BINARY ADDITION

            The basic rules for binary addition are listed in the table below:

                      Case                      Input                      Sum                      Carry
                        1                       0 + 0                       0                         0

                        2                       0 + 1                       1                         0

                        3                       1 + 0                       1                         0

                        4                       1 + 1                       0                         *1

            *Carry of 1 is shifted to the next column to the left of the current digit.

            Example 1                           Example 2                           Example 3

            Compute (101)  + (100)              Compute (1011)  + (1101)            Compute (11111)  + (1001)
                            2       2                            2         2                           2         2
                                                          1 1 1     Carry                   1 1 1 1     Carry
                     1 0 1                               1 0 1 1                           1 1 1 1 1
                   + 1 0 0                             + 1 1 0 1                           + 1 0 0 1
                   1 0 0 1                             1 1 0 0 0                         1 0 1 0 0 0


            BINARY SUBTRACTION

            The basic rules for binary subtraction are listed in the table below:

                      Case                       Input                      Sum                      Carry
                        1                        0 – 0                       0                         0

                        2                        1 – 0                       1                         0

                        3                        1 – 1                       0                         0
                        4                        0 – 1                       1                        *1


            * To subtract a higher digit from a lower digit, i.e., 1 from 0, one has to borrow from the left column.


            Example 1                           Example 2                                Example 3

            Compute (1110)  + (101)   2         Compute (10101)  + (1010)   2                Compute (11101)  + (10011) 2
                                                                                                        2
                                                                  2
                             2
                             0 10                          0 10 0 10                                    0  10
                        1 1  1  0                        1  0  1  0  1                          1  1  1  0  1
                         – 1 0 1                          – 1  0  1  1                         – 1  0  0  1  1
                        1 0 0 1                             1  0  1  1                           0  1  0  1  0



            BINARY MULTIPLICATION
            The Binary multiplication is similar to the decimal multiplication. It is simpler than decimal multiplication
            because only 0 and 1 are involved. The basic rules for binary multiplication are listed in the table below:



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