The 9's complement of a number is calculated by subtracting 9 fromĀ every digit of that number.
Now, in this case, (9-3)(9-8)(9-1) gives us the 9's complement which is (6)(1)(8) i.e. 618.
Now, in this case, (9-3)(9-8)(9-1) gives us the 9's complement which is (6)(1)(8) i.e. 618.
