Page 18 - computer science (868) class 11
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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. It is used to define memory locations and
colours on web pages. It is also used to represent Media Access Control (MAC) addresses.
Definition
The base of hexadecimal number system is 16. This system has numerals 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
and 15. But 10 to 15 being two-digit numbers are represented by single 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 of any number system into another number system. For example, a decimal number can be
converted into binary, octal, hexadecimal and vice versa. Let us discuss the conversion of a number from one number
system to another.
1616 Touchpad Computer Science-XI

