Problem: a dishonest dealer professes to sell goods at the cost price but uses a weight of 720 grams per kg , what is his percent ?
Rationale: "explanation : 720 - - - 280 100 - - - ? = > 38.9 % answer : c"
annotated_formula: subtract(multiply(divide(const_100, 720), multiply(const_100, multiply(add(const_3, const_2), const_2))), const_100)