a) Convert the decimal number - 238 into a signed binary number using

(1) sign-magnitude method (2) 1's complement method (3) 2's complement method (1 + 1 + 1 = 3 marks)

b) If the above decimal number is positive , that is + 238, then convert it to a signed binary number using 1 's complement method (1 mark)

c) Do the following binary subtraction: (3 marks)

1 0 1 0 1 0 0 0 1 . 1 1 1 1 1 -

0 1 0 0 1 0 0 0 1 . 1 0 1 1 1