Let’s Try (r-1)’s and r’s complement. How to get (r-1)’s complement of decimal number…?
Say r =10
How do we get (r-1)’s complement …?
(r-1)′s i.e. 9’s complement of decimal number can be obtained by ((10n – 1)-number)
where n represents the number of digits in the given number.
Example 1: Find 9’s complement of (1234)10
9′s complement = 104-1-1234 = 9999-1234 = 8765
How do we get (r)’s complement …?
r’s i.e. 10’s complement can be obtained by (10n – number)
where n represents the number of digits in the given number.
Example 2: Find 10′s complement = 104-1234 = 8766.
Now that we have learned to convert decimal numbers to their 9′s & 10′s complements, we will move to subtraction using them. Remember always the number to be subtracted or the negative number is converted to 9′s or 10′s complement.
(r-1)’s and r’s complement examples
