when 1 / 20 % of 8000 is subtracted from 1 / 10 of 8000 , the difference is
1 / 20 % of 8000 = 4 1 / 10 of 8000 = 800 800 - 2 = 798 ans : d
subtract(divide(8000, 10), divide(8000, multiply(20, const_100)))