a train 125 m long passes a man , running at 10 km / hr in the same direction in which the train is going , in 10 sec . the speed of the train is ?
"speed of the train relative to man = 125 / 10 = 25 / 2 m / sec . = 25 / 2 * 18 / 5 = 45 km / hr let the speed of the train be x km / hr . then , relative speed = ( x - 10 ) km / hr . x - 10 = 45 = > x = 55 km / hr . answer : c"
divide(divide(subtract(125, multiply(multiply(10, const_0_2778), 10)), 10), const_0_2778)