Which 8-bit two's complement value correctly represents the denary number –19?

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Question

Which 8-bit two's complement value correctly represents the denary number –19?

Accepted Answer

B: 11101101 — +19 in binary is 00010011. Inverting gives 11101100, then adding 1 gives 11101101, which is –19. Option A is incorrect as it does not follow the two's complement method. Option C is simply +19 (positive). Option D is the one's complement (inversion only, without adding 1).

Answer

A: 10010011

Answer

D: 11101100

Answer

C: 00010011

Answer

B: 11101101

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