Difficulty: Easy
Correct Answer: A-4, B-3, C-1, D-2
Explanation:
Introduction / Context:
Digital systems frequently require quick translation between decimal and binary. This problem reinforces binary conversion for common values, ensuring confidence when reading registers, bitmaps, or instruction encodings.
Given Data / Assumptions:
Concept / Approach:
Convert each decimal number to binary using successive division by 2 or by decomposing into powers of 2. Then match to the list of 8-bit patterns.
Step-by-Step Solution:
Verification / Alternative check:
Hex cross-check: 45 = 0x2D = 0010 1101; 90 = 0x5A = 0101 1010; 180 = 0xB4 = 1011 0100; 210 = 0xD2 = 1101 0010. Hex-to-binary mapping confirms the 8-bit strings.
Why Other Options Are Wrong:
Each incorrect option mis-assigns at least one decimal-to-binary mapping, which will break in arithmetic or bit-test verification.
Common Pitfalls:
Dropping leading zeros (acceptable visually but confusing in fixed-width contexts) or mixing nibble order when transcribing hex to binary.
Final Answer:
A-4, B-3, C-1, D-2
Discussion & Comments