Find the 4-digit complement of a) 0232 b) 9644 3. The attempt at a solution I'm not really sure what is being asked here. When asked what form the numbers were given in and whether the problem was talking about 9's complement, his response was "the answer is 9's complement". So I don't really know what to do since they appear to be in 9's complement form already. Does anyone think they can help?