What is the largest 16-bit binary value that can be represented by:
(a) Unsigned number
(b) Signed magnitude
(c) Signed two’s complement
The Correct Answer and Explanation is:
Here are the correct answers for the largest 16-bit binary values under each representation:
(a) Unsigned Number:
Answer: 1111111111111111 (binary) = 65,535 (decimal)
(b) Signed Magnitude:
Answer: 0111111111111111 (binary) = 32,767 (decimal)
(c) Signed Two’s Complement:
Answer: 0111111111111111 (binary) = 32,767 (decimal)
✅ Explanation (300+ words):
The number of bits (in this case, 16 bits) determines how many binary values can be represented. Each of the three number formats interprets the same 16-bit binary sequence differently:
(a) Unsigned Number:
In an unsigned representation, all 16 bits are used to represent the magnitude of the number. There is no sign bit (i.e., no bit is used to indicate positive or negative).
- The smallest unsigned value is
0000000000000000= 0. - The largest unsigned value is when all bits are 1s:
1111111111111111. - This binary number is equal to: $$
2^{16} – 1 = 65,535
$$
So, the largest 16-bit unsigned binary number is 65,535.
(b) Signed Magnitude:
In signed magnitude representation, the first bit is the sign bit:
0indicates a positive number.1indicates a negative number.- The remaining 15 bits represent the magnitude.
The largest positive number in signed magnitude is:
0followed by 151s:0111111111111111- This represents: $$
2^{15} – 1 = 32,767
$$
So, the largest 16-bit signed magnitude number is 32,767.
(c) Signed Two’s Complement:
In two’s complement representation:
- The first bit is still the sign bit, but the negative numbers are represented differently (using inversion and addition of 1).
- The range for a 16-bit two’s complement number is: $$
-2^{15} \text{ to } 2^{15} – 1
$$ That is: $$
-32,768 \text{ to } 32,767
$$ - The largest number is when the sign bit is 0 and the remaining bits are all 1s:
0111111111111111= 32,767
📌 Summary Table:
| Representation | Largest 16-bit Value | Decimal Equivalent |
|---|---|---|
| Unsigned | 1111111111111111 | 65,535 |
| Signed Magnitude | 0111111111111111 | 32,767 |
| Signed Two’s Complement | 0111111111111111 | 32,767 |
Each format has a different range because of how it uses the bits, particularly the most significant bit (MSB).