a train is 510 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 = 510 + 140 = 650 meter time = distance / speed = 650 * ( 2 / 25 ) = 52 seconds answer : c"
divide(add(510, 140), divide(multiply(45, const_1000), const_3600))