Number System MCQ Quiz - Objective Question with Answer for Number System - Download Free PDF
Last updated on Jun 23, 2025
Latest Number System MCQ Objective Questions
Number System Question 1:
147 in base 10 when converted to hexadecimal system will be:
Answer (Detailed Solution Below)
Number System Question 1 Detailed Solution
Answer: Option 3
Explanation:
Step 1: first we convert 147 to the Binary number system.
(147)10 = (10010011)2
Step 2: Now we group 4 bits to convert the Hexadecimal number system.
1001 0011
≡ (93)16
Number System Question 2:
The decimal equivalent of a binary number 1001110 is:
Answer (Detailed Solution Below)
Number System Question 2 Detailed Solution
Convert binary to decimal :-
- For binary number with n digits:
- dn-1 ... d3 d2 d1 d0
- The decimal number is equal to the sum of binary digits (dn) times their power of 2 (2n):
- decimal = d0×20 + d1×21 + d2×22 + ...
Calculation:
Decimal equivalent of binary number 1001110 :-
= 1 × 26 + 0 x 25 + 0 x 24 + 1 x 23 + 1 x 22 + 1 x 21 + 0 x 20
= 64 + 0 + 0 + 8 + 4 + 2 + 0 = 78
Number System Question 3:
The binary representation of 129.25 is _____ .
Answer (Detailed Solution Below)
Number System Question 3 Detailed Solution
Binary to decimal conversion →
(129)10 = (10000001)2
0.25 → 0.25 × 2 = 0.5
0.5 × 2 = 1
(0.25)10 = (.01)2
(129.25)10 = (10000001.01)2
Number System Question 4:
The Octal equivalent of the binary number 1011101011 is:
Answer (Detailed Solution Below)
Number System Question 4 Detailed Solution
Answer: Option 2
Explanation:
An octal Equivalent of a binary number is obtained by grouping 3 bits from right to left.
001 | 011 | 101 | 011 |
1 | 3 | 5 | 3 |
So Octal Equivalent: 1353
Important Points
Binary to Octal code
000 |
001 |
010 |
011 |
100 |
101 |
110 |
111 |
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
Number System Question 5:
Which of the following is the correct octal representation of the hexadecimal number 1A3?
Answer (Detailed Solution Below)
Number System Question 5 Detailed Solution
Explanation:
Hexadecimal to Octal Conversion
Definition: Hexadecimal and octal are both positional numeral systems, widely used in computing and digital electronics. Hexadecimal (base-16) uses sixteen symbols, 0-9 and A-F, to represent values, while octal (base-8) uses eight symbols, 0-7.
To convert a hexadecimal number to its octal equivalent, it is often easiest to first convert it to binary (base-2), and then from binary to octal. This method works because both octal and hexadecimal are powers of 2 (octal is 23 and hexadecimal is 24).
Step-by-Step Solution:
Given hexadecimal number: 1A3
1. Convert Hexadecimal to Binary:
Each hexadecimal digit can be represented by a 4-bit binary number:
- 1 (Hex) = 0001 (Binary)
- A (Hex) = 1010 (Binary)
- 3 (Hex) = 0011 (Binary)
So, the hexadecimal number 1A3 can be written in binary as: 0001 1010 0011
2. Group Binary Digits into Sets of Three:
Since octal is base-8 and each octal digit corresponds to 3 binary digits, we group the binary digits in sets of three, starting from the right:
- 0001 1010 0011 (Binary)
- 000 110 100 011 (Binary, grouped in sets of three)
3. Convert Binary Sets to Octal:
Each group of three binary digits can be converted directly to its octal equivalent:
- 000 (Binary) = 0 (Octal)
- 110 (Binary) = 6 (Octal)
- 100 (Binary) = 4 (Octal)
- 011 (Binary) = 3 (Octal)
So, the binary number 000 110 100 011 can be written in octal as: 0643
Hence, the correct octal representation of the hexadecimal number 1A3 is 643.
Important Information:
To analyze other options, let's convert the hexadecimal number 1A3 using the same method:
- Option 1: 346
- 346 (Octal) in binary: 011 100 110
- Groups: 011 100 110 (Binary) = 3 4 6 (Octal)
- Binary to Hexadecimal: 011100110 (Binary) = 1C6 (Hex)
- 1C6 ≠ 1A3
- Option 2: 124
- 124 (Octal) in binary: 001 010 100
- Groups: 001 010 100 (Binary) = 1 2 4 (Octal)
- Binary to Hexadecimal: 001010100 (Binary) = 54 (Hex)
- 54 ≠ 1A3
- Option 3: 634
- 634 (Octal) in binary: 110 011 100
- Groups: 110 011 100 (Binary) = 6 3 4 (Octal)
- Binary to Hexadecimal: 110011100 (Binary) = 19C (Hex)
- 19C ≠ 1A3
Therefore, the correct option is confirmed as option 4: 643.
Top Number System MCQ Objective Questions
Binary number 101110110 is equal to decimal number _______.
Answer (Detailed Solution Below)
Number System Question 6 Detailed Solution
Download Solution PDF- The correct answer is option 3, i.e., 374.
- Binary number 101110110 is equal to decimal number 374.
- Following method can be used to convert Binary number to Decimal number:
- (101110110)2 = (1 x 28) + (0 x 27) + (1 x 26) + (1 x 25) + (1 x 24) + (0 x 23) + (1 x 22) + (1 x 21) + (0 x 20)
- (101110110)2 = 256 + 0 + 64 + 32 + 16 + 0 + 4 + 2 + 0
- (101110110)2 = 374
One megabyte In base 2 (binary) Is equivalent to .
Answer (Detailed Solution Below)
Number System Question 7 Detailed Solution
Download Solution PDFThe correct answer is 220 bytes.
Key Points
- 1 Megabyte is equal to 1000000 bytes (decimal).
- 1 MB = 106 B in base 10 (SI).
- 1 Megabyte is equal to 1048576 bytes (binary).
- 1 MB = 220 B in base 2.
- Byte is the basic unit of digital information transmission and storage, used extensively in information technology, digital technology, and other related fields. It is one of the smallest units of memory in computer technology, as well as one of the most basic data measurement units in programming.
- The earliest computers were made with the processor supporting 1 byte commands, because in 1 byte you can send 256 commands. 1 byte consists of 8 bits,
- Megabyte (MB) is a unit of transferred or stored digital information, which is extensively used in information and computer technology.
- In SI, one megabyte is equal to 1,000,000 bytes. At the same time, practically 1 megabyte is used as 220 B, which means 1,048,576 bytes.
The Octal equivalent of the binary number 1011101011 is:
Answer (Detailed Solution Below)
Number System Question 8 Detailed Solution
Download Solution PDFAnswer: Option 2
Explanation:
An octal Equivalent of a binary number is obtained by grouping 3 bits from right to left.
001 | 011 | 101 | 011 |
1 | 3 | 5 | 3 |
So Octal Equivalent: 1353
Important Points
Binary to Octal code
000 |
001 |
010 |
011 |
100 |
101 |
110 |
111 |
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
The number of 1s in the binary representation of (3 ⋆ 4096 + 15 ⋆ 256 + 5 ⋆ 16 + 3) are
Answer (Detailed Solution Below)
Number System Question 9 Detailed Solution
Download Solution PDFApplication:
Decimal value = (3 ⋆ 4096 + 15 ⋆ 256 + 5 ⋆ 16 + 3)
It can be written as:
(2 + 1) × 212 + (8 + 4 + 2 + 20) × 28 + (4 + 1) × 24 + (2 + 1) × 20
21 × 212 + 20 × 212 + (23 + 22 + 21 + 20) × 28 + (22 + 20) × 24 + (21 + 20) × 20
This can be written as:
213 + 212 + 211 + 210 + 29 × 28 + 26 + 24 + 21 + 20
The binary representation will be:
(11111101010011)2
The 12th digit in standard hexadecimal system is equal to:
Answer (Detailed Solution Below)
Number System Question 10 Detailed Solution
Download Solution PDF
Mistake PointsThe question is asking for the 12th Digit in Hexadecimal representation, i.e. 0 will be the first digit, 1 will be the second, and so on.
The correct answer is (option 2) i.e. B
Explanation:
Digits in hexadecimal number systems are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F. Therefore, the total number of different digits in hexadecimal number systems is 16.
Hence 12th digit in the hexadecimal system is B. And it is equivalent to 11 for Decimal and 1011 for the Binary number system,
Important Points
- Digits in decimal number systems are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. Therefore, number of different digits in decimal number systems is 10.
- Digits in Octal number systems are 0, 1, 2, 3, 4, 5, 6, 7. Therefore, number of different digits in octal number systems is 8.
- Digits in binary number systems are 0, 1. Therefore, number of different digits in binary number systems is 2.
- In the standard hexadecimal system, each digit can have 16 possible values, ranging from 0 to 9 and then A to F, representing the values 10 to 15.
- To determine the 12th digit in the standard hexadecimal system, we need to convert the number 12 from decimal to hexadecimal.
- 12 in decimal is equal to B in hexadecimal. Therefore, the 12th digit in the standard hexadecimal system is option 4) B.
The hexadecimal system is a number system with a base of 16. It is commonly used in computing and digital systems because it provides a convenient way to represent binary numbers. In hexadecimal, the digits range from 0 to 9, and then use the letters A to F to represent values 10 to 15.
Here's a breakdown of the digits leading up to the 12th position:
- 1st digit: 0
- 2nd digit: 1
- 3rd digit: 2
- 4th digit: 3
- 5th digit: 4
- 6th digit: 5
- 7th digit: 6
- 8th digit: 7
- 9th digit: 8
- 10th digit: 9
- 11th digit: A
- 12th digit: B
Therefore, the 12th digit in the standard hexadecimal system is 'B'.
The hexadecimal equivalent of the decimal number 4096 is ____.
Answer (Detailed Solution Below)
Number System Question 11 Detailed Solution
Download Solution PDFConcept:
- To convert a decimal number system to hexadecimal, we follow the successive division approach i.e. we divide the decimal number by 16 and note down the remainder.
- Each remainder is then expressed in hexadecimal.
Calculation:
So, The hexadecimal equivalent of decimal number 4096 is 1000.
Excess - 3 - code is also known as
Answer (Detailed Solution Below)
Number System Question 12 Detailed Solution
Download Solution PDFExcess - 3 - code is also known as self-complementing code which means 1's complement of an excess - 3 number is the excess - 3 code for the 9's complement of the corresponding decimal number.
Example:
1 in binary is 0001
excess 3 code is 0001 + 0011 = 0100
1's complement of the above code is 1011 which is 11
11 is excess 3 code for 8
and 9's complement of 1 is 8
Decimal |
Excess – 3 code |
Binary |
Gray code |
Octal |
0 |
0011 |
0000 |
0000 |
000 |
1 |
0100 |
0001 |
0001 |
001 |
2 |
0101 |
0010 |
0011 |
010 |
3 |
0110 |
0011 |
0010 |
011 |
4 |
0111 |
0100 |
0110 |
100 |
5 |
1000 |
0101 |
0111 |
101 |
6 |
1001 |
0110 |
0101 |
110 |
7 |
1010 |
0111 |
0100 |
111 |
8 |
1011 |
1000 |
1100 |
001 000 |
Answer (Detailed Solution Below)
Number System Question 13 Detailed Solution
Download Solution PDFThe correct answer is option 4.
Concept:
Hexadecimal number system:
The hexadecimal number system is a kind of number system with a base value of 16 characters. It is also spelled 'hex' at times. Only 16 symbols are used to represent hexadecimal values. These are the values or symbols: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, and F. Each number corresponds to a decimal value.
Octal Number System:
The Octal Number System has an eight-digit basis and employs numbers ranging from 0 to 7. When paired in pairs of three, octal numbers are commonly represented as binary numbers in the number system.
Explanation:
The given data,
If (356)8 = (x)16
Convert the octal number to binary and then convert it into Hexa decimal.
3= 011
5= 101
6= 110
(011 101 110)2= (0 1110 1110)2
1110= E
(0 E E)16
Hence the correct answer is EE.
Alternate Method The given data,
If (356)8 = (x)16
Convert the octal number to decimal and then convert it into Hexa decimal.
(356)8 =(3 x 82+ 5 x 81+6 x 80)10
(356)8 =(238)10
(356)8 =(238)10 =(EE)16
Which type of number system is represented by base 8?
Answer (Detailed Solution Below)
Number System Question 14 Detailed Solution
Download Solution PDFNumber System
The octal number system is represented by base 8.
Number System |
Base |
Maximum no. of bits |
Range |
Binary |
2 |
2 |
0-1 |
Decimal |
10 |
4 |
0-9 |
Octal |
8 |
3 |
0-7 |
Hexadecimal |
16 |
4 |
0-15 |
What is the binary number for decimal number 9?
Answer (Detailed Solution Below)
Number System Question 15 Detailed Solution
Download Solution PDFThe number system is a way to represent or express numbers. You have heard of various types of number systems such as the whole numbers and the real numbers. But in the context of computers, we define other types of number systems. They are:
- The decimal number system
- The binary number system
- The octal number system and
- The hexadecimal number system
Binary Number System:
- A binary number system is one of the four types of number system.
- In computer applications, where binary numbers are represented by only two symbols or digits, i.e. 0 (zero) and 1(one).
- The binary numbers here are expressed in the base-2 numeral system.
- For example, (101)2 is a binary number. Each digit in this system is said to be a bit.
Here we will show you step-by-step how to convert the decimal number 9 to binary.
Step 1) Divide 9 by 2 to get the Quotient. Keep the Whole part for the next step and set the Remainder aside.
Step 2) Divide the Whole part of the Quotient from Step 1 by 2. Again, keep the Whole part and set the Remainder aside.
Step 3) Repeat Step 2 above until the Whole part is 0.
Step 4) Write down the Remainders in reverse order to get the answer to 9 as a binary.
Important Points
Here we will show our work so you can follow along:
Decimal Number |
Operation |
Quotient |
Remainder |
Binary Number |
9 |
÷ 2 |
4 |
1 |
1 |
4 |
÷ 2 |
2 |
0 |
01 |
2 |
÷ 2 |
1 |
0 |
001 |
1 |
÷ 2 |
0 |
1 |
1001 |
Therefore, Binary equivalent of decimal number 9 is 1001.