Number Systems and Codes Questions and Answers
Number Systems and Codes Questions with Answers form the foundation of digital electronics reasoning and aptitude exams. This topic includes binary, octal, decimal, and hexadecimal number conversions, along with coding systems like Gray, ASCII, and BCD. Competitive exams such as GATE, DRDO, and ISRO often test candidates’ logical understanding of number representation and digital computation. Practicing reasoning questions and answers with step-by-step solutions builds numerical reasoning and circuit analysis confidence. Each question is structured to test clarity on base conversions, weighted codes, and arithmetic operations. With these aptitude-based questions, you can easily master the numerical logic behind digital systems. Download the PDF and start your reasoning test practice online today.
Number Systems and Codes
61. The binary number 101110101111010 can be written in octal as ________.
- 515628
- 565778
- 656278
- 565728
63. Convert the decimal number 151.75 to binary.
- 10000111.11
- 11010011.01
- 00111100.00
- 10010111.11
64. Convert the following octal number to binary. 1048
- 0010001002
- 1000000012
- 00101002
- 10000012
65. 3428 is the decimal value for which of the following binary-coded decimal (BCD) groupings?
- 11010001001000
- 11010000101000
- 011010010000010
- 110100001101010
66. The binary-coded decimal (BCD) system can be used to represent each of the 10 decimal digits as a(n):
- 4-bit binary code
- 8-bit binary code
- 16-bit binary code
- ASCII code
67. The decimal number 18 is equal to the binary number ________.
- 11110
- 10001
- 10010
- 1111000
68. The 2's complement of 11100111 is ________.
- 11100110
- 00011001
- 00011000
- 00011010
69. Convert the following decimal number to BCD. 469
- 100101101000
- 010001101001
- 100001101001
- 100101100100
70. Express the decimal number –37 as an 8-bit number in sign-magnitude.
- 10100101
- 00100101
- 11011000
- 11010001