BCD encoding — check the claim for decimal 73: Binary-Coded Decimal (BCD) represents each decimal digit with its 4-bit binary code. Evaluate: “The BCD equivalent of 73 is 01001001.”

Introduction / Context:
BCD is widely used in digital displays and financial systems because it preserves each decimal digit explicitly. Each decimal digit 0–9 maps to a 4-bit binary pattern. This question verifies whether you can encode a two-digit decimal number into standard (8421) BCD.

Given Data / Assumptions:

• Use straight (8421) BCD: 0→0000, 1→0001, …, 9→1001.
• Each decimal digit is encoded independently into 4 bits.
• No parity, sign nibble, or excess-3 code is used.

Concept / Approach:
For 73, the tens digit is 7 and the ones digit is 3. Encode each digit to 4 bits and concatenate tens before ones. Therefore: 7→0111 and 3→0011, yielding 0111 0011.

Step-by-Step Solution:
Identify digits: 7 and 3.Map 7 → 0111; map 3 → 0011.Concatenate: 0111 0011.Compare to claim 0100 1001 (which corresponds to decimal 49 in BCD). The claim is incorrect.

Verification / Alternative check:
Check table: 7=0111, 3=0011. The provided 0100 1001 equals 4=0100 and 9=1001 → decimal 49, not 73.

Why Other Options Are Wrong:
“Correct” is wrong for straight BCD. Terms like “packed BCD with parity” or “excess-3” describe different encodings and still would not match 0100 1001 for 73.

Common Pitfalls:
Confusing BCD with binary of the whole number (73₁₀ = 1001001₂) or with ASCII codes for characters.

Final Answer:
Incorrect (correct BCD is 0111 0011)