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Say any octal number 2345.067 can be represented as,

8 3 8 2 8 1 8 0 8 -1 8 -2 8 -3
2 3 4 5 . 0 6 7

1.1.4 Hexadecimal Number System
Hexadecimal numbers provide a more human-friendly representation. They are used to define memory locations and
colours on web pages. They are also used to represent Media Access Control (MAC) addresses.

Definition

The base of the hexadecimal number system is 16. This system has numerals 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and the symbols
A, B, C, D, E and F. The values 10 to 15 are represented by the alphabetic characters A, B, C, D, E and F. It is also a
positional value-based system where each digit has its weight denoted as a power of 16.

For example, any hexadecimal number A2DF.37C can be represented as,

16 3 16 2 16 1 16 0 16 -1 16 -2 16 -3
A 2 D F . 3 7 C

Following table shows the relationship among different number systems:

Decimal Binary Octal Hexa
0 0 0 0 0 0 0
1 0 0 0 1 1 1
2 0 0 1 0 2 2
3 0 0 1 1 3 3
4 0 1 0 0 4 4

5 0 1 0 1 5 5
6 0 1 1 0 6 6
7 0 1 1 1 7 7
8 1 0 0 0 10 8
9 1 0 0 1 11 9
10 1 0 1 0 12 A
11 1 0 1 1 13 B
12 1 1 0 0 14 C
13 1 1 0 1 15 D
14 1 1 1 0 16 E
15 1 1 1 1 17 F

1.2 NUMBER SYSTEM CONVERSION
We can convert a number from any number system into another number system. For example, a decimal number can
be converted into binary, octal or hexadecimal and vice versa. Let us discuss the conversion of a number from one
number system to another.

18 Touchpad Computer Science (Ver. 3.0)-XI