Addition and subtraction of numbers in base 2 - JSS1 Mathematics Lesson Note

Adding binary numbers follows similar rules to decimal addition, but with simpler carry rules (only 0 or 1). For example:

  101   (5 in decimal)

+ 011   (3 in decimal)

------

  1000  (8 in decimal, 1 carried over to the next column)

Subtraction in binary also follows similar principles as decimal subtraction but may require borrowing from higher place values. For example:

  101   (5 in decimal)

-  011   (3 in decimal)

------

   010   (2 in decimal)