Problem: how long does a train 60 m long travelling at 60 kmph takes to cross a bridge of 80 m in length ?
Rationale: "b 16.8 sec d = 60 + 80 = 140 m s = 60 * 5 / 18 = 50 / 3 t = 140 * 3 / 50 = 8.4 sec answer is b"
annotated_formula: divide(add(60, 80), multiply(60, const_0_2778))