ALU 101 Binary Number Systems 2 — Questions and Answers
Question 1: What is 1101 + 0110 in binary?
- 10010
- 10011 (Correct answer)
- 10100
- 10001
Correct answer: 10011
1101 + 0110 = 10011 in binary (carry propagates to produce a 5-bit result of 19).
Question 2: The one's complement of binary 10110 is:
- 01001 (Correct answer)
- 01010
- 10110
- 11001
Correct answer: 01001
One's complement is obtained by inverting every bit: 10110 → 01001.
Question 3: In an 8-bit signed two's complement system, what is the range of representable integers?
- -128 to 127 (Correct answer)
- -127 to 127
- -255 to 255
- 0 to 255
Correct answer: -128 to 127
An 8-bit two's complement number can represent values from −128 (10000000) to +127 (01111111).
Question 4: Converting decimal 45 to binary gives:
- 101011
- 101101 (Correct answer)
- 110101
- 101110
Correct answer: 101101
45 ÷ 2 repeated gives remainders 1,0,1,1,0,1 (reading bottom-up) = 101101.
Question 5: What does BCD stand for in digital number representation?
- Binary Coded Decimal (Correct answer)
- Binary Circuit Design
- Bit Count Data
- Base Conversion Digit
Correct answer: Binary Coded Decimal
BCD stands for Binary Coded Decimal, where each decimal digit is represented by a 4-bit binary group.
Question 6: Which representation is used to simplify subtraction in ALU hardware?
- Sign-magnitude
- One's complement
- Two's complement (Correct answer)
- BCD
Correct answer: Two's complement
Two's complement is used in ALU hardware because subtraction can be performed as addition of a negative number without special circuitry.
ALU 101 Binary Number Systems 2
What is 1101 + 0110 in binary?