Page 12 - TrackpadV5.1_class7
P. 12

OCTAL NUMBER SYSTEM
                  A number system made up of eight digits from 0 to 7, is known as the octal number system.

                  When the octal number system is used, every number is formed using 0,1,2,3,4,5,6 and 7. The
                  base of the octal number system is 8. It is also known as the base-8 system. Each positioning
                  number represents the power of base 8. The place value of the digits according to position and
                  weight is as follows:

                     Position          2              1            0                            -1            -2
                                                                                  .
                     Weights           8 2           8 1           8 0                         8 -1          8 -2

                  For example: (1763) 8

                         3
                                  2
                                            1
                  = (1 x 8 ) + (7 x 8 ) + (6 x 8 ) + (3 x 8 )
                                                      0
                  = (1 x 512) + (7 x 64) + (6 x 8) + (3 x 1)
                  = 512 + 448 + 48 + 3
                  = 1011 or (1011) 10


                  HEXADECIMAL NUMBER SYSTEM
                  A number system made up of sixteen symbols, 0 to 9, and A to F is known as the hexadecimal
                  number system. When the hexadecimal number system is used, every number is formed using
                  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F, where A = 10, B = 11, C = 12, D = 13, E = 14, and F = 15.
                  The base of the hexadecimal number system is 16. It is also known as the base-16 system. Each

                  position represents a power of base 16. The place value of the digits according to position and
                  weight is as follows:

                     Position          2              1            0              .             -1            -2

                     Weights          16 2           16 1          16 0                        16 -1         16 -2

                  For Example: (2AF)  16

                                               0
                                     1
                          2
                  = (2 x 16 ) + (A x 16 ) + (F x 16 )
                  = (2 x 256) + (10 x 16) + (15 x 1)
                  = 512 + 160 + 15

                  = 687

                  The hexadecimal  number  system  has  made  the  representation  of  large  values  easy.  The
                  hexadecimal numbers are used to represent colours on a webpage, that's why programmers
                  now prefer hexadecimal numbers. Some examples of colour code are:
                     Red: #FF0000

                     Green: #00FF00

                     Blue: #0000FF




                   10   Pro (V5.1)-VII
   7   8   9   10   11   12   13   14   15   16   17