a train running at the speed of 30 km / hr crosses a pole in 9 sec . what is the length of the train ?
"speed = 30 * 5 / 18 = 25 / 3 m / sec length of the train = speed * time = 25 / 3 * 9 = 75 m answer : a"
multiply(divide(multiply(30, const_1000), const_3600), 9)