125%
IT never will unless you subtract or multiply. But, if you're adding in binary (base 2), AND you are not using a carry, then the bit that you are working with will: In binary: 1 equals one, 10 equals...
The answer is 15, try using a calculator next time. Windows has one built-in.
-1+1=0.
I don't know maybe it could be 3 or 4 NO IT IS 2 OBVIOUSLY