TITLE: How can I convert 2's complement to decimal?
QUESTION [18 upvotes]: Suppose I have the 2's complement, negative number 1111 1111 1011 0101 (0xFFBB5).  How can I represent this as a decimal number in base 10?

REPLY [7 votes]: A very simple way of converting 2's complement negative number to decimal.
Let a number 11010110,
so the decimal representation of it is,
 –2^7 + 2^6 + 2^4 + 2^2 + 2^1 = – 128 + 64 + 16 + 4 + 2 = – 42
the idea is same as converting a normal binary number to decimal but with a negative sign with left most binary digit.