a train passes a station platform in 48 sec and a man standing on the platform in 40 sec . if the speed of the train is 36 km / hr . what is the length of the platform ?
"speed = 36 * 5 / 18 = 10 m / sec . length of the train = 10 * 40 = 400 m . let the length of the platform be x m . then , ( x + 400 ) / 48 = 10 = > x = 80 m . answer : a"
multiply(40, multiply(36, const_0_2778))