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2.9 BINARY ARITHMETIC                                                61


                    Consider the following simple example for the division operation, which will be carried
                  out in both decimal and binary:

                                         DD_ _ r0.375"| _ ro.011"|
                                            ~          ~


                  EXAMPLE 2.31 In decimal:

                                     a = 1 - D s = 0.5

                                     k Q = 1 +a = 1.5
                                         D sk Q = 0.75
                                     *i = l + (0.75)ioc = 1.25

                                         D skoki = 0.9375.
                                     k 2 = 1 + (0.9375) ioc = 1-0625
                                         D sk 0kik 2 = 0.99609375

                                     fc 3 = 1 + (0.99609375)  10C = 1.00390625
                                         D sk 0kik 2k3 = 0.999984741.

                    Therefore, after four iterations the quotient becomes


                              Q = D Dk 0kik 2ki =0.749988556
                                                                           6
                                                                          ~
                                            = 0.749989 rounded to six places (10~).
                    Note that a fifth iteration with Jk 4 = 1.000015259 produces Q = 0.750000 rounded to
                  six places.
                  In binary:


                                     a = l -D 5 = 0.1
                                    k Q = l+a = 1.1



                                         1+(0.11) 2 C = 1.01
                                               =0.1111
                                                     = 1-0001


                                                         = 1.00000001

                                                  = 0.1111111111111111.
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