if price of t . v set is reduced by 25 % , then its sale increases by 75 % , find net effect on sale value
"- a + b + ( ( - a ) ( b ) / 100 ) = - 25 + 75 + ( - 25 * 75 ) / 100 = - 25 + 75 - 19 = 31 answer : a"
multiply(subtract(multiply(divide(subtract(const_100, 25), const_100), divide(add(const_100, 75), const_100)), const_1), const_100)