A good answer might be:

1000 1100 (correct)

The number to be subtracted is negated by the usual means, as in the previous problem. Then the "binary addition algorithm" is used:

11100 111         
 1110 0101    == -27d
 1010 0111    == -89d
 ---------      -----
 1000 1100      -116d

Since the carry into the most significant column is the same as the carry out of that column the result is correct. The answer came out negative, but that is fine.

No! Not More Practice Subtraction!

A computer does several million of these per second. Surely you can do another one?

QUESTION 32:

Subtract 0111 1000 from 1011 0000 Is the result correct or not?