a watch was sold at a loss of 9 % . if it was sold for rs . 220 more , there would have been a gain of 4 % . what is the cost price ?
"91 % 104 % - - - - - - - - 13 % - - - - 220 100 % - - - - ? = > rs . 1692 answer : e"
divide(multiply(220, const_100), subtract(add(const_100, 4), subtract(const_100, 9)))