#### Problem Statement

In the octal system, we have grouped every 3 bits of a binary number.

But on the computer, the memory allocation always happens in multiples of 4.

Like, 1 Byte (8 bits), 4 Byte (32 bits).

#### Solution - Hexadecimal Number System

In the hexadecimal number system, we group every 4 binary bits. So that we can easily represent computer memory addresses.

Possible values that can be formed using 4 bit is 15 (1111)2.

Itâ€™s also called as base 16 number system.

Binary

Decimal

0000

0

0

0001

1

1

0010

2

2

0011

3

3

0100

4

4

0101

5

5

0110

6

6

0111

7

7

1000

8

8

1001

9

9

1010

10

A or a

1011

11

B or b

1100

12

C or c

1101

13

D or d

1110

14

E or e

1111

15

F or f

The hexadecimal number system will use letters A to F to represent numbers 10 to 15.

10-A,11-B,12-C,13-D,14-E,15-F

Let's convert (10001101) 2 into hexadecimal format.

Group every 4 binary bits from right to left.

Finally, combine the results.

(10001101) 2

(1000) (1101)

(1000) = (8)

(1101) = (13) ==> 13 -> D

(1000) (1101) = (8D)16

#### Pictorial Explanation

If the number of bits is not multiples of 4. Add zeros before the binary number to make it perfect 4-bit group.

#### Example

(101010) 2

Here, the number of bits is 6. By adding two zeros before the binary number, we can make it multiples of 4.

Like,(00101010) 2.

To convert the hexadecimal number into binary, we need to represent every hexadecimal digit into 4 binary bits.

Finally, combine the binary bits.

#### Example

Let's convert (FD) 16 into binary numbers

(FD) 16

F= (1111)

D= (1101)

(FD) 16 = (11111101) 2