We can add the binary numbers 11112 and 1102 similar to the way we add the decimal numbers 1510 and 610.



  1. First, we add the numbers in the rightmost column. One plus zero adds to 1.
    01111
  + 00110
        1
  1. Now we add the next column. One plus one adds to 102, so we carry the one to the next column and write the zero under this column.
      1 
    01111
  + 00110
       01
  1. Notice that the third column now contains three ones. Adding the first two ones gives us 102. Adding this sum to the remaining one gives us a total of 112, so we carry a one to the next column and write one under this column.
     11 
    01111
  + 00110
      101
  1. The two ones in the fourth column add to 102, so we carry a one to the final column, and write zero below this column.
    111 
    01111
  + 00110
     0101
  1. Finally, the carry from the previous column plus the two zeros from this column add to 1.
    111 
    01111
  + 00110
    10101
  1. This gives us a final answer of 101012.
    111 
    01111
  + 00110
    10101

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