Subtraction of numbers in base 2 - JSS1 Mathematics Lesson Note

Subtracting binary numbers involves borrowing similar to decimal subtraction. If the number being subtracted is larger than the number it is being subtracted from, borrowing from the next higher place value (just like in decimal) is necessary. For example:

   1010   (10 in decimal)

-  011    (3 in decimal)

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    111    (7 in decimal)