Parity bit calculation — append an even parity bit to a 6-bit word Given the data word 110010, determine the 7-bit result after adding an even parity bit (total number of 1s must be even).
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A1110010
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B1111001
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C110010
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D001101
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E0110010
Answer
Correct Answer: 1110010
Explanation
Introduction / Context:Parity is a lightweight error-detection method used in memories, serial links, and legacy buses. With even parity, the parity bit is chosen so that the total count of 1s in the transmitted word (data + parity) is even. This question checks your ability to compute and append an even parity bit correctly.
Given Data / Assumptions:
- Data word: 110010 (6 bits).
- Even parity requirement: total number of 1s across all 7 bits must be even.
- Parity bit is appended as an extra bit; its exact position (MSB vs LSB) is implementation-defined, but options indicate it is prefixed to create a 7-bit result.
Concept / Approach:Count the 1s in the data and add 1 if the count is odd (to make it even). If the count is already even, add 0. Here we prepend the computed parity bit (consistent with the presented choices).
Step-by-Step Solution:
Count ones in 110010: 1 + 1 + 0 + 0 + 1 + 0 = 3 (odd).Even parity requires an additional 1 to make the total count even.Place parity bit as the new MSB: 1 110010 ⇒ 1110010.Verification / Alternative check:Recount 1s in 1110010: there are 4 ones, which is even. If the system appended the bit at the LSB instead, the 7-bit sequence would be 1100101; however, the given options reflect the MSB placement, so 1110010 is the correct choice here.
Why Other Options Are Wrong:
- 1111001, 001101, 0110010: each yields the wrong total parity or scrambles the original bit order.
- 110010: contains no parity bit and still has an odd count of ones.
Common Pitfalls:
- Losing track of where the parity bit is appended; match the convention implied by the answer choices.
- Confusing even and odd parity definitions.
Final Answer:1110010