### A good answer might be:

- (correct result:) The carry into the left column is the SAME as the carry out.

# Carry In == Carry Out

With two's comp repn the result of addition is correct if the carry into the high order column is the same as the carry out of the high order column. The carry can be one or zero. Overflow is detected by comparing two bits, an easy thing to do with electronics. Here are some more examples:

No Overflow | No Overflow | Overflow | Overflow
--- | --- | --- | ---
    11111 111
     0011 1111  ( 6310)
     1101 0101  (-4310)
     ---------
     0001 0100  ( 2010)
    00000 011
     1100 0001  ( -6310)
     0010 1011  (  4310)
     ---------
     1110 1100  ( -2010)
    01111 100
     0011 1111  (  6310)
     0110 0100  ( 10010)
     ---------
     1010 0011  ( -9310)
    10000 000
     1100 0001  ( -6310)
     1001 1100  (-10010)
     ---------
     0101 1101  (  9310)

### QUESTION 24:

Perform the "binary addition algorithm" on the following 8-bit two's complement numbers. Is the result correct or not?

>      1011 1101
>      1110 0101
>      ---------