1.1   Number Bases (Part 4)

(F) Addition and Subtraction of Two Numbers in Base Two
1. In the addition of two numbers in base two, the following rules applied:
 
  0+ 0= 02
  0+ 1= 12
  1+ 0= 12
  1+ 1= 102
  1+ 1+ 1= 10+ 1= 112
 
2. In the subtraction of two numbers in base two, the following rules applied:
 
  0– 0= 02
  1– 0= 12
  1– 1= 02
  10– 1= 12
   

Example 2:
 
Find the value of each of the following:
(a) 11012 + 1102
(b) 110012 + 101002
(c) 110112 – 11012
(d) 10002 – 1012
 
Solution:
(a)


(b)


(c) 



(d)



Calculator Computation
You may obtain the answer directly from a scientific calculator by pressing:
[MODE]   [MODE]   [3 (BASE)]
Key in the following:
(a)
[ BIN ] 1101 [ + ] 110 [ = ] 
The screen display is: [ 10011 ]
(b)
[ BIN ] 11001 [ + ] 11100 [ = ] 
The screen display is: [ 110101 ]
(c)
[ BIN ] 11011  ] 1101 [ = ] 
The screen display is: [ 1110 ]
(d)
[ BIN ] 1000  ] 101 [ = ] 
The screen display is: [ 11 ]