Austrian Method of Subtraction

How do you subtract 5592 from 11149. Simple question....

There's an interesting method which involves only addition as it is easier to do than subtraction. Add from the amount to be subtracted upto the next higher unit, then to the next and so on.

Example 5592 + 8 = 5600. 5600 + 400 = 6000. 6000 + 5000 = 11000. 11000 + 149 = 11149.
so the answer is 8+400+5000+149 = 5557.