What is the 2’s complement of (−28)₁₀ in 16-bit representation?
2021
What is the 2’s complement of (−28)₁₀ in 16-bit representation?
- A.
1000000000011100
- B.
1111111111100011
- C.
1111111111100100
- D.
1111111111100101
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Correct answer: C
To find the 16-bit 2’s complement representation of $(-28)_{10}$, we follow a standard three-step process:
1. Convert the absolute value to binary
First, find the binary representation of 28.
28 = 16 + 8 + 4
In binary: 11100
For a 16-bit representation, pad with leading zeros:
0000 0000 0001 1100
2. Find the 1's complement
Invert all the bits (change 0s to 1s and 1s to 0s):
1111 1111 1110 0011
3. Find the 2's complement
Add 1 to the 1's complement result:
1111 1111 1110 0011 + 1 = 1111 1111 1110 0100.
The 16-bit 2’s complement of (−28)₁₀ is 1111 1111 1110 0100.