Find 2s compliment 427 12 bits long for example 000000000000
     Find 2\'s compliment  -427 (12 bits long for example 000000000000)  1111100110000  00011010101010  111001010100  111001010101 
  
  Solution
-427
negative numbers can be represented by 2\'s complement
convert 42710 to binary
remainders
2|427
2|213 1
2|106 1
2|53 0
2|26 1
2|13 0
2|6 1
2|3 0
2|1 1
2|0 1
= 110101011
= 0001 1010 1011
= 1110 0101 0100 (1s complement)
+1 (2\'s complement)
= 1110 0101 0101
Hence (4.111001010101) is correct option.

