i bought two books ; for rs . 300 . i sold one at a loss of 15 % and other at a gain of 19 % and then i found each book was sold at the same price . find the cost of the book sold at a loss ?
"x * ( 85 / 100 ) = ( 300 - x ) 119 / 100 x = 175 answer : a"
divide(multiply(300, add(const_100, 19)), add(subtract(const_100, 15), add(const_100, 19)))