Decimal to BCD — Digitwise Encoding Convert the decimal number 469 into straight BCD by encoding each decimal digit as a 4-bit binary code and concatenating the results.

Introduction / Context:
Binary Coded Decimal (BCD) represents each decimal digit independently using a 4-bit code. This preserves decimal structure for display and financial calculations at the cost of storage efficiency. The task is to produce straight BCD, not packed with delimiters, by simple digitwise mapping.

Given Data / Assumptions:

• Decimal input: 469.
• Use straight BCD mapping: 0→0000 through 9→1001.
• Concatenate digit codes in the same order as the original number.

Concept / Approach:
Break the decimal number into digits, encode each digit into its 4-bit BCD representation, and then join the codes. No arithmetic conversion to pure binary is required for BCD; this is a symbol by symbol mapping process.

Step-by-Step Solution:
1) Split 469 into digits: 4, 6, 9.2) Encode: 4→0100, 6→0110, 9→1001.3) Concatenate: 0100 0110 1001 → 010001101001.4) Result is the straight BCD form.

Verification / Alternative check:
Confirm by reading back the 4-bit groups: 0100=4, 0110=6, 1001=9. The round trip returns the original decimal digits without ambiguity.

Why Other Options Are Wrong:

• 100101101000, 100001101001, 100101100100: These are incorrect encodings or reordered groupings and do not map to 4, 6, 9 as required.

Common Pitfalls:
Using pure binary for the entire number instead of per digit mapping, or forgetting that codes 1010–1111 are invalid in straight BCD.

Final Answer:
010001101001