Problem: how long does a train 250 meters long running at the rate of 72 km / hr take to cross a bridge 150 meters in length ?
Rationale: "distance = length of train + length of bridge = 250 + 150 = 400 speed = 72 km / hr = 72 * 5 / 18 = 20 m / s required time = 400 / 20 = 20 seconds answer is b"
annotated_formula: divide(add(250, 150), multiply(72, const_0_2778))