Coding systems — identify the primary advantage of BCD over straight binary. Question: What is the main practical benefit of Binary Coded Decimal (BCD) when compared with pure binary representation?
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AFewer bits are required to represent a decimal number with the BCD code.
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BThe relative ease of converting to and from decimal.
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CBCD codes are easily converted to hexadecimal codes.
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DBCD codes are easily converted to straight binary codes.
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EBCD allows arithmetic faster than binary on all CPUs.
Answer
Correct Answer: The relative ease of converting to and from decimal.
Explanation
Introduction / Context:BCD (Binary Coded Decimal) encodes each decimal digit separately in 4 bits. While it is less storage-efficient than straight binary, it simplifies human-centric decimal tasks such as display, entry, and rounding in financial computations.
Given Data / Assumptions:
- Comparing BCD vs straight binary
- Focus on practical advantage for everyday systems
Concept / Approach:BCD’s strength lies in easy decimal digit isolation and conversion. Each 4-bit group maps directly to one decimal digit (0–9), making formatting and decimal I/O trivial. Straight binary packs value efficiently but requires repeated division/modulus by 10 to extract digits.
Step-by-Step Explanation:
BCD: one nibble = one decimal digit ⇒ easy display/entryBinary: must convert by arithmetic operations to get decimal digitsTherefore, BCD simplifies conversion to/from decimalVerification / Alternative check:Consider a decimal cash amount like 123.45. In BCD, each digit is independently represented, easing precise decimal rounding and avoiding some binary/decimal conversion pitfalls.
Why Other Options Are Wrong:
- Fewer bits: false; BCD uses more bits than straight binary.
- Easy to hex or straight binary: not the primary advantage; conversion exists but is not inherently simpler than decimal I/O.
- Arithmetic faster: CPU-dependent and generally false; binary arithmetic is typically faster and smaller.
Common Pitfalls:
- Assuming BCD is more efficient; it is more convenient for decimal, not more compact.
Final Answer:The relative ease of converting to and from decimal.