Problem: what is the angle between the hands of a clock when time is 10 : 30 ?
Rationale: "angle between two hands = 30 h - 11 / 2 m = 30 * 10 - 30 * 11 / 2 = 300 - 165 = 135 deg answer : e"
annotated_formula: subtract(multiply(30, multiply(const_3, const_2)), 10)