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Hexadecimal equivalent of 10001111.0111 is
                                                                              1
                                                                  3
                                                                                   0
                                                                        2
                        1000     1111        .       0111       8(2 ) 4(2 ) 2(2 ) 1(1 )             Hexa
                         8         F         .        7          1     0     0    0       1 × 8 + 0 × 4 + 0 × 2 + 0 × 1 = 8
                                                                 1     1     1    1       1 × 8 + 1 × 4 + 1 × 2 + 1 × 1 = 15
                                                                 0     1     1    1       0 × 8 + 1 × 4 + 1 × 2 + 1 × 1 = 7
                     (217.34)  = (8F.7)
                           8      16
                 12.  Convert (C1D.B)  to octal.
                                  16
                Ans.
                      C(12)   1      D      .      B
                      1100   0001   1101    .    1011
                      Binary equivalent is (110000011101.1011)
                                                       2
                      Converting 110 000 011 101.101 100 to octal
                                                                                    1
                                                                              2
                                                                                         0
                       110    000   011    101     .     101        100     4(2 ) 2(2 ) 1(1 )          Octal
                        6     0      3      5      .      5          4       1     1    0       1 × 4 + 1 × 2 + 0 × 1 = 6
                                                                             0     0    0       0 × 4 + 0 × 2 + 0 × 1 = 0
                                                                             0     1    1       0 × 4 + 1 × 2 + 1 × 1 = 3
                                                                             1     0    1       1 × 4 + 0 × 2 + 1 × 1 = 5
                                                                             1     0    0       1 × 4 + 0 × 2 + 0 × 1 = 4
                      (6035.54)
                            8
                 13.  Perform the following Binary addition.
                      (1001.1)  + (110110.11)  + (10.1) 2
                                       2
                           2
                Ans.    +1  +1  +1  +1  +1   +1  +1
                                    1    0   0    1   .   1
                           1    1   0    1   1    0   .   1   1
                       +                     1    0   .   1
                       1   0    0   0    0   1    0   .   1   1

                      (1000010.11) 2
                 14.  Perform binary subtraction (100110.01)  - (10111.1)  using.
                                                               2
                                                     2
                      a.  Borrow method
                      b.  1’s Complement method
                      c.   2’s Complement method
                Ans.  a.      +1    +1      +1     +1    +1     +1
                              1      0      0      1      1     0  -1  .   0     1

                         -           1      0      1      1      1    .    1
                              0      0      1      1      1      0    .    1     1
                         Discarding leading 0’s
                        (1110.11) 2

                     b.  1’s complement of 010111.10 is 101000.01  +1                                  +1
                        Adding 100110.01 and 101000.01, we get       1    0     0    1     1    0   .   0    1
                        Discarding MSB 1 and leading 0’s        +    1    0     1    0     0    0   .   0    1
                                                                1    0    0     1    1     1    0   .   1    0
                                                                                                             1
                        (1110.11) 2                                  0    0     1    1     1    0   .   1    1





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