NCERT Computer Science Class 11 - Chapter 2 Solutions - part2

 

Chapter 2 - Encoding Schemes and Number System


NCERT Solutions



Exercise Solutions  ( continued .. )


6. Express the following decimal numbers to hexadecimal numbers:

(i) 548

Steps:

548 ÷ 16 = 34, remainder 4

34 ÷ 16 = 2, remainder 2

2 ÷ 16 = 0, remainder 2


Thus 548 is 224 in Hexadecimal


(ii) 4052

Steps:

4052 ÷ 16 = 253, remainder 4

253 ÷ 16 = 15, remainder 13 (which is represented as D in hexadecimal)

15 ÷ 16 = 0, remainder 15 (which is represented as F in hexadecimal)

Thus 4052 is FD4 in Hexadecimal



(iii) 58

Steps:

58 ÷ 16 = 3, remainder 10 (which is represented as A in hexadecimal)

3 ÷ 16 = 0, remainder 3


Thus 58 is 3A in Hexadecimal


(iv) 100.25


Step 1: Convert the Integer Part (100)

100 ÷ 16 = 6, remainder 4

6 ÷ 16 = 0, remainder 6


Step 2: Convert the Fractional Part (0.25)

Multiply by 16:

0.25 × 16 = 4.0


Thus 100.25 in Hexadecimal is 64.4




7. Express the following hexadecimal numbers into equivalent decimal numbers.

(i) 4A2

Identify the positions and their values:

The hexadecimal number is read from right to left, where each digit's position corresponds to a power of 16.

The digits in 4A2 are:

  • 22 in the 160 (ones) place
  • AA (which is 10 in decimal) in the 161 (sixteens) place
  • 4 in the 162 (two hundred fifty-sixes) place

Calculate the decimal value for each digit:

        2 × 160 = 2 × 1 = 2

        10 × 161 = 10 × 16 = 160

        4 × 162 = 4 × 256 = 1024


Sum all the values:

        1024 + 160 + 2 = 1186 


Thus 4A2 in Decimal is 1186


(ii) 9E1A

Calculate decimal value for each digit:

        9 × 163 = 9 × 4096 = 36864

        14 × 162 = 14 × 256 = 3584

        1 × 161 = 1 × 16 = 16

        10 × 160 = 10 × 1 = 10

Sum all the values:  40474


(iii)  6BD

Calculate decimal value for each digit:

        6 × 162 = 6 × 256 = 1536

        11 × 161 = 11 × 16 = 176

        13 × 160 = 13 × 1 = 13

Sum all the values: 1725



(iv)  6C.34

Calculate decimal value for integer part (6C)

6 × 161 = 6 × 16 = 96
12 × 160 = 12 × 1 = 12


Convert the fractional part (.34)

        3 × 16−1   =   0.1875
        4 × 16−2  =  0.015625  

Sum all values and combine both parts to get the answer: 108.203125.



8. Convert the following binary numbers into octal and hexadecimal numbers.

(i) 1110001000
Convert to Decimal first: 904

Now, convert 904 to Octal: 

        904 ÷ 8 = 113 with a remainder of 0
        113 ÷ 8 = 14 with a remainder of 1
        14 ÷ 8 = 1 with a remainder of 6
        1 ÷ 8 = 0 with a remainder of 1


Octal value: 1610

Now, convert 904 to Hexadecimal:
        
        904 ÷ 16 = 56 with a remainder of 8
        56 ÷ 16 = 3 with a remainder of 8
        3 ÷ 16 = 0 with a remainder of 3

Hexadecimal value: 388


(ii)  110110101

Convert to Decimal first: 437

Now convert 437 to Octal:

        437 ÷ 8 = 54 with a remainder of 5
        54 ÷ 8 = 6 with a remainder of 6
        6 ÷ 8 = 0 with a remainder of 6

Octal value: 665

Now convert 437 to Hexadecimal:

        437 ÷ 16 = 27 with a remainder of 5
        27 ÷ 16 = 1 with a remainder of 11 (which is represented as B in hexadecimal)
        1 ÷ 16 = 0 with a remainder of 1

Hexadecimal value: 1B5


(iii)  1010100

Convert to Decimal first: 84

Now convert 84 to Octal: 

        84 ÷ 8 = 10 with a remainder of 4
        10 ÷ 8 = 1 with a remainder of 2
        1 ÷ 8 = 0 with a remainder of 1

Octal value: 124

Now convert 84 to Hexadecimal:

        84 ÷ 16 = 5 with a remainder of 4
        5 ÷ 16 = 0 with a remainder of 5

Hexadecimal value: 54


(iv)  1010.1001

Convert to Decimal first: 10.5625

Now convert 10.5625 to Octal:

Integer Part:

        10 ÷ 8 = 1 with a remainder of 2
        1 ÷ 8 = 0 with a remainder of 1

Fractional Part:

        0.5625 × 8 = 4.5 (Take the integer part, which is 4)
        0.5 × 8 = 4.0 (Take the integer part, which is 4)

Octal value: 12.44

Now convert 10.5625 to Hexadecimal

Integer Part:

        10 ÷ 16 = 0 with a remainder of 10 (which is represented as A in hexadecimal)

Fractional Part:

        0.5625 × 16 = 9.0 (Take the integer part, which is 9)

Hexadecimal value: A.9




Comments