Question

Express each of the following signed numbers (2’s complement format) in decimal: 1001 1001; 0111 0111; 1000 0101

Answer 1

When converting 2's complement to decimal, you know if it's negative or not by the left-most bit. If it is "0", then it is positive and just convert it as if it were an unsigned value. If it is "1", you can negate it in the same way as you would to turn a positive number to a negative number. That will give you the opposite of the negative.