the tax on a commodity is diminished by 40 % but its consumption is increased by 25 % . find the decrease percent in the revenue derived from it ?
"100 * 100 = 10000 60 * 125 = 7500 10000 - - - - - - - 2500 100 - - - - - - - ? = 25 % answer : c"
subtract(const_100, divide(multiply(add(const_100, 25), subtract(const_100, 40)), const_100))