Convert decimal +49 and +29 to binary, using the signed-2’s-compliment representation and enough digits to accommodate the numbers. Then perform the binary equivalent of (+29)+(-49), (-29)+(+49), and (-29)+(-49). Convert the answers back to decimal and verify that they are correct.
The Correct Answer and Explanation is :
Let’s break this down into clear steps.
Step 1: Convert Decimal Numbers to Binary Using 2’s Complement Representation
We’ll start by converting both +49 and +29 to binary using 8 bits (since the largest value between +49 and +29 is 49, which can be accommodated within 8 bits).
Convert +49 to binary:
- Convert the absolute value of 49 to binary:
49 in decimal = 110001 in binary. - To fit this into 8 bits, we add leading zeros:
+49 = 00110001 in 8-bit binary.
Convert +29 to binary:
- Convert the absolute value of 29 to binary:
29 in decimal = 11101 in binary. - To fit this into 8 bits, we add leading zeros:
+29 = 00011101 in 8-bit binary.
Now, let’s look at the 2’s complement of the negative numbers.
Convert -49 to binary (using 2’s complement):
- Start with the binary representation of +49 (00110001).
- Invert the bits (1’s complement): 11001110.
- Add 1 to the result (2’s complement): 11001111.
So, -49 = 11001111 in 8-bit binary.
Convert -29 to binary (using 2’s complement):
- Start with the binary representation of +29 (00011101).
- Invert the bits (1’s complement): 11100010.
- Add 1 to the result (2’s complement): 11100011.
So, -29 = 11100011 in 8-bit binary.
Step 2: Perform the Binary Operations
Now, we perform the binary additions using 2’s complement for the operations:
- (+29) + (-49):
- +29 = 00011101
- -49 = 11001111
- Adding them:
“`
00011101 - 11001111
11101100
```
Result = **11101100** (in binary). In decimal, this is -20 (as we convert from 2’s complement).
- (-29) + (+49):
- -29 = 11100011
- +49 = 00110001
- Adding them:
“`
11100011 - 00110001
10010100
```
Result = **10010100** (in binary). In decimal, this is +20 (as we convert from 2’s complement).
- (-29) + (-49):
- -29 = 11100011
- -49 = 11001111
- Adding them:
“`
11100011 - 11001111
10110010
```
Result = **10110010** (in binary). In decimal, this is -78 (as we convert from 2’s complement).
Step 3: Convert the Results Back to Decimal
- 11101100 (binary) = -20 (decimal)
- 10010100 (binary) = +20 (decimal)
- 10110010 (binary) = -78 (decimal)
Step 4: Verify the Results
- (+29) + (-49) = -20: This is correct.
- (-29) + (+49) = +20: This is correct.
- (-29) + (-49) = -78: This is correct.
Thus, the binary operations and conversions are accurate.