a train is 310 meter long is running at a speed of 45 km / hour . in what time will it pass a bridge of 140 meter length ?
"speed = 45 km / hr = 45 * ( 5 / 18 ) m / sec = 25 / 2 m / sec total distance = 310 + 140 = 500 meter time = distance / speed = 450 * ( 2 / 25 ) = 36 seconds answer : a"
divide(add(310, 140), divide(multiply(45, const_1000), const_3600))