a train running at a speed of 36 km / h passes an electric pole in 15 seconds . in how many seconds will the whole train pass a 380 - meter long platform ?
"let the length of the train be x meters . when a train crosses an electric pole , the distance covered is its own length x . speed = 36 km / h = 36000 m / 3600 s = 10 m / s x = 15 * 10 = 150 m . the time taken to pass the platform = ( 150 + 380 ) / 10 = 53 seconds the answer is d ."
divide(add(multiply(multiply(36, const_0_2778), 15), 380), multiply(36, const_0_2778))