What is the 15's complement of the hexadecimal number (C00D0)16?
2018
What is the 15's complement of the hexadecimal number (C00D0)16?
Answer: B. (3FF2F)16 — ConceptFor an n-digit hexadecimal number, the 15's complement is formed by replacing every digit d with F − d, where F represents 15. This digitwise rule…
- A.
(2FF3F)16
- B.
(3FF2F)16
- C.
(3EE2E)16
- D.
(2EE3E)16
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Show answer & explanation
Correct answer: B
Concept
For an n-digit hexadecimal number, the 15's complement is formed by replacing every digit d with F − d, where F represents 15.
This digitwise rule makes each original digit and its complement add to F without carrying to an adjacent position.
Application
For the first digit C: F − C = 3.
For each zero: F − 0 = F.
For the digit D: F − D = 2.
For the final zero: F − 0 = F.
Keeping the original order gives (3FF2F)16.
Cross-check
Adding the original number and the complement gives (C00D0)16 + (3FF2F)16 = (FFFFF)16; every position sums to F, confirming the result.