Decimal part of 99 is 0 so u have to borrow 1 from 99.

And add to 0. But after decimal it becomes ten.further borrow 1 till u get to right last 0.now subtract 2 from 10.its 8; subtract 9 from 9; again subtract 9 from 9; subtract 3 from 9.(all this should be from right to left).