# Number Systems and Codes MCQ Questions & Answers

Number Systems and Codes MCQs : This section focuses on the "Number Systems and Codes". These Multiple Choice Questions (MCQs) should be practiced to improve the Number Systems and Codes skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.

Question 1

The number of bits used to store a BCD digit is:

A. 8
B. 4
C. 1
D. 2

Question 2

The weight of the LSB as a binary number is:

A. 1
B. 2
C. 3
D. 4

Question 3

Convert the binary number 1001.0010 to decimal.

A. 125
B. 12.5
C. 90.125
D. 9.125

Question 4

Convert 110010012 (binary) to decimal.

A. 201
B. 2001
C. 20
D. 210

Question 5

What is the result when a decimal 5238 is converted to base 16?

A. 327.375
B. 12166
C. 1388
D. 1476

Question 6

What is the decimal value of the hexadecimal number 777?

A. 191
B. 1911
C. 19
D. 19111

Question 7

What is the resultant binary of the decimal problem 49 + 1 = ?

A. 1010101
B. 110101
C. 110010
D. 110001

Question 8

Convert the decimal number 151.75 to binary.

A. 10000111.11
B. 11010011.01
C. 111100
D. 10010111.11

Question 9

3428 is the decimal value for which of the following binary coded decimal (BCD) groupings?

A. 1.101E+13
B. 1.101E+13
C. 1.101E+13
D. 1.101E+14

Question 10

Convert the binary number 1011010 to hexadecimal.

A. 5B
B. 5F
C. 5A
D. 5C

Question 11

What is the difference between binary coding and binary coded decimal?

A. Binary coding is pure binary.
B. BCD is pure binary.
C. Binary coding has a decimal format.
D. BCD has no decimal format.

Question 12

Base 10 refers to which number system?

A. binary coded decimal
B. decimal
C. octal

Question 13

Sample-and-hold circuits in ADCs are designed to:

A. sample and hold the output of the binary counter during the conversion process
B. stabilize the ADCs threshold voltage during the conversion process
C. stabilize the input analog signal during the conversion process
D. sample and hold the ADC staircase waveform during the conversion process

Question 14

3 × 101 + 7 × 100 is equal to ________.

A. 3.7
B. 37
C. 10
D. 370

Question 15

3428 is the decimal value for which of the following binary-coded decimal (BCD) groupings?

A. 1.10E+13
B. 1.10E+13
C. 1.10E+13
D. 1.10E+14

Question 16

A binary number's value changes most drastically when the ________ is changed.

A. MSB
B. frequency
C. LSB
D. duty cycle

Question 17

A decimal 11 in BCD is ________.

A. 1011
B. 1100
C. 10001
D. 10010

Question 18

Alphanumeric codes should include as a minimum:

A. the capacity to represent the alphabet upper- and lowercase characters and the decimal numbers in a straight binary format.
B. the capacity to code all possible decimal numbers in a direct octal representation of BCD codes.
C. the alphabet upper- and lowercase letters, the decimal digits, the seven punctuation marks, and other characters or symbols.
D. the ability to represent decimal numbers greater than 12810 in a straight binary format.

Question 19

An analog signal has a range from 0 V to 5 V. What is the total number of analog possibilities within this range?

A. 5
B. 50
C. 250
D. infinite

Question 20

An informational signal that makes use of binary digits is considered to be:

A. solid state
B. digital
C. analog
D. non-oscillating

Question 21

Assign the proper even parity bit to the code 1100001.

A. 11100001
B. 1100001
C. 1100001
D. 1110101

Question 22

Assign the proper odd parity bit to the code 111001.

A. 1111011
B. 1111001
C. 111111
D. 11111

Question 23

A. 121035
B. CA35
C. 53AC1
D. 530121

Question 24

Convert 17318 to decimal.

A. 216.4
B. 985
C. 3D9
D. 1123

Question 25

A. 711
B. 2C7
C. 811
D. 1C9

Question 26

Convert 52716 to binary.

A. 343
B. 1101000111
C. 10100100111
D. 11100100101

Question 27

Convert 5278 to binary.

A. 11100111
B. 101010111
C. 343
D. 111010101

Question 28

Convert 59.7210 to BCD.

A. 111011
B. 1011001.011
C. 1110.11
D. 1.01E+14

Question 29

Convert 73116 to decimal.

A. 216.4
B. 985
C. 3D9
D. 1841

Question 30

Convert 8B3F16 to binary.

A. 35647
B. 11010
C. 1.01E+15
D. 1.00E+15

Question 31

Convert binary 01001110 to decimal.

A. 4E
B. 78
C. 76
D. 116

Question 32

A. 916
B. 1116
C. 10116
D. 1016

Question 33

A. 8F16
B. CE16
C. DF16
D. CF16

Question 34

A. EE216
B. FF216
C. 2FE16
D. FD216

Question 35

Convert decimal 213 to binary.

A. 11001101
B. 11010101
C. 1111001
D. 11100011

Question 36

Convert decimal 64 to binary.

A. 1010010
B. 1000000
C. 110110
D. 1001000

Question 37

A. 1.10E+11
B. 1.10E+11
C. 1.10E+11
D. 1.10E+11

Question 38

Convert hexadecimal value 16 to decimal.

A. 2210
B. 1610
C. 1010
D. 2010

Question 39

Convert hexadecimal value C1 to binary.

A. 11000001
B. 1000111
C. 111000100
D. 111000001

Question 40

Convert the binary number 1001.00102 to decimal.

A. 90.125
B. 9.125
C. 125
D. 12.5

Question 41

Convert the binary number 1100 to Gray code.

A. 11
B. 1010
C. 1100
D. 1001

Question 42

Convert the following BCD number to decimal.010101101001bcd

A. 539
B. 2551
C. 569
D. 1552

Question 43

Convert the following BCD number to decimal.100000000011bcd

A. 8003
B. 803
C. 1003
D. 103

Question 44

Convert the following binary number to decimal. 010112

A. 11
B. 35
C. 15
D. 10

Question 45

Convert the following binary number to decimal. 100110102

A. 154
B. 155
C. 153
D. 157

Question 46

Convert the following binary number to octal. 0011010112

A. 1538
B. 3518
C. 2538
D. 3528

Question 47

Convert the following binary number to octal. 0101111002

A. 1728
B. 2728
C. 1748
D. 2748

Question 48

Convert the following decimal number to 8-bit binary.187

A. 101110112
B. 110111012
C. 101111012
D. 101111002

Question 49

Convert the following decimal number to 8-bit binary.35

A. 100102
B. 100112
C. 1000112
D. 1000102

Question 50

Convert the following decimal number to BCD.127

A. 11100100001
B. 111010001
C. 1010111
D. 100100111

Question 51

Convert the following decimal number to BCD.469

A. 1.00E+11
B. 10001101001
C. 1.00E+11
D. 1.00E+11

Question 52

Convert the following decimal number to hexadecimal.125

A. 7D16
B. D716
C. 7C16
D. C716

Question 53

Convert the following decimal number to hexadecimal.74

A. A416
B. B416
C. 4A16
D. 4B16

Question 54

Convert the following decimal number to octal.281

A. 1348
B. 4318
C. 3318
D. 1338

Question 55

Convert the following decimal number to octal.39

A. 638
B. 368
C. 478
D. 748

Question 56

Convert the following hexadecimal number to binary. 14B16

A. 1.01E+12
B. 1010010112
C. 1010011012
D. 1.10E+12

Question 57

Convert the following hexadecimal number to binary.C916

A. 101110012
B. 101110112
C. 100111002
D. 110010012

Question 58

Convert the following hexadecimal number to decimal.1CF16

A. 463
B. 4033
C. 479
D. 4049

Question 59

Convert the following hexadecimal number to decimal.B516

A. 212
B. 197
C. 165
D. 181

Question 60

Convert the following octal number to binary.1048

A. 10001002
B. 1000000012
C. 101002
D. 10000012

Question 61

Convert the following octal number to binary.768

A. 1101112
B. 1111102
C. 1111002
D. 1001112

Question 62

Convert the following octal number to decimal. 178

A. 51
B. 82
C. 57
D. 15

Question 63

Convert the following octal number to decimal. 358

A. 71
B. 17
C. 92
D. 29

Question 64

Convert the Gray code 1011 to binary.

A. 1011
B. 1010
C. 100
D. 1101

Question 65

Decode the following ASCII message. 1010011101010010101011000100101100101000001001000100000110100101000100

A. STUDYHARD
B. STUDY HARD
C. stydyhard
D. study hard

Question 66

Determine the decimal equivalent of the signed binary number 11110100 in 1's complement.

A. 116
B. –12
C. 11
D. 128

Question 67

Digital electronics is based on the ________ numbering system.

A. decimal
B. octal
C. binary

Question 68

Express the decimal number –37 as an 8-bit number in sign-magnitude.

A. 10100101
B. 100101
C. 11011000
D. 11010001

Question 69

Hexadecimal letters A through F are used for decimal equivalent values from:

A. 1 through 6
B. 9 through 14
C. 10 through 15
D. 11 through 17

Question 70

How many BCD code bits and how many straight binary bits would be required to represent the decimal number 643?

A. 12 BCD, 12 binary
B. 12 BCD, 10 binary
C. 12 BCD, 9 binary
D. 16 BCD, 9 binary

Question 71

How many binary digits are required to count to 10010?

A. 7
B. 2
C. 3
D. 100

Question 72

How many bits are in an ASCII character?

A. 16
B. 8
C. 7
D. 4

Question 73

If a typical PC uses a 20-bit address code, how much memory can the CPU address?

A. 20 MB
B. 10 MB
C. 1 MB
D. 580 MB

Question 74

One hex digit is sometimes referred to as a(n):

A. byte
B. nibble
C. grouping
D. instruction

Question 75

Select one of the following statements that best describes the parity method of error detection.

A. Parity checking is best suited for detecting single-bit errors in transmitted codes.
B. Parity checking is not suitable for detecting single-bit errors in transmitted codes.
C. Parity checking is capable of detecting and correcting errors in transmitted codes.
D. Parity checking is best suited for detecting double-bit errors that occur during the transmission of codes from one location to another.

Question 76

The 1's complement of 10011101 is ________.

A. 1100010
B. 10011110
C. 1100001
D. 1100011

Question 77

The 2's complement of 11100111 is ________.

A. 11100110
B. 11001
C. 11000
D. 11010

Question 78

The American Standard Code for Information Interchange (ASCII) uses how many individual pulses for any given character?

A. 1
B. 2
C. 7
D. 8

Question 79

The base of the hexadecimal system is:

A. eight.
B. sixteen.
C. ten.
D. two.

Question 80

The BCD number for decimal 16 is ________.

A. 10110
B. 10000
C. 10010
D. 11100000

Question 81

The BCD number for decimal 347 is ________.

A. 1100 1011 1000
B. 0011 0100 0111
C. 0011 0100 0001
D. 1100 1011 0110

Question 82

The binary number 101110101111010 can be written in octal as ________.

A. 515628
B. 565778
C. 656278
D. 565728

Question 83

The binary number 11001110 is equal to the decimal number ________.

A. 12
B. 206
C. 127
D. 66

Question 84

The binary number 1110 is equal to the decimal number ________.

A. 3
B. 1
C. 7
D. 14

Question 85

The binary number 11101011000111010 can be written in hexadecimal as ________.

A. DD63A16
B. 1D63A16
C. 1D33A16
D. 1D63116

Question 86

The binary number for F3A16 is ________.

A. 1.11E+11
B. 1.11E+11
C. 111010
D. 11000100

Question 87

The binary number for octal 458 is ________.

A. 100010
B. 100101
C. 110101
D. 100100

Question 88

The binary-coded decimal (BCD) system can be used to represent each of the 10 decimal digits as a(n):

A. 4-bit binary code
B. 8-bit binary code
C. 16-bit binary code
D. ASCII code

Question 89

The decimal number 18 is equal to the binary number ________.

A. 11110
B. 10001
C. 10010
D. 1111000

Question 90

The decimal number 188 is equal to the binary number ________.

A. 10111100
B. 111000
C. 1100011
D. 1111000

Question 91

The decimal number for octal 748 is ________.

A. 74
B. 60
C. 22
D. 62

Question 92

The difference of 111 – 001 equals ________.

A. 100
B. 111
C. 1
D. 110

Question 93

The octal number for binary 1101110101110110 is ________.

A. 6545218
B. 5565618
C. 1566568
D. 1565668

Question 94

The octal numbering system:

B. groups binary numbers in groups of 4
C. saves time
D. simplifies tasks and saves time

Question 95

The sum of 11101 + 10111 equals ________.

A. 110011
B. 100001
C. 110100
D. 100100

Question 96

The sum of the two BCD numbers, 0011 + 0011, is ________.

A. 110
B. 111
C. 11
D. 1100

Question 97

The voltages in digital electronics are continuously variable.

A. TRUE
B. FALSE

Question 98

What decimal number does 25 represent?

A. 10
B. 31
C. 25
D. 32

Question 99

What is the difference between binary coding and binary-coded decimal?

A. BCD is pure binary.
B. Binary coding has a decimal format.
C. BCD has no decimal format.
D. Binary coding is pure binary.

Question 100

What is the result when a decimal 5238 is converted to base 16?

A. 327.375
B. 12.166
C. 1388
D. 1476

Question 101

What is the resultant binary of the decimal problem 49 + 01 = ?

A. 1010101
B. 110101
C. 110010
D. 110001

Question 102

When using even parity, where is the parity bit placed?

A. Before the MSB
B. After the LSB
C. In the parity word
D. After the odd parity bit

Question 103

When using the repeated division by 2 method of converting from decimal to binary, one must write the first remainder as the:

A. MSB
B. MSB, provided the following sequence of remainders are written in descending order until the final remainder is achieved.
C. LSB
D. LSB, provided the final remainder is used to replace the original LSB, which is then moved to the MSB position.

Question 104

Which is not a word size?

A. 64
B. 28
C. 16
D. 8

Question 105

Which is typically the longest: bit, byte, nibble, word?

A. Bit
B. Byte
C. Nibble
D. Word

Question 106

Which of the following is an invalid BCD code?

A. 11
B. 1101
C. 101
D. 1001

Question 107

Which of the following is the most widely used alphanumeric code for computer input and output?

A. Gray
B. ASCII
C. Parity
D. EBCDIC