How many seconds will a train 250 meters long take to cross a platform 200 meters long if the speed of the train is 90 kmph? Pick:  A) 18 sec  B) 15 sec  C) 21 sec  D) 16 sec  E) 20 sec

Rationale: "d = 250 + 200 = 450 s = 90 * 5 / 18 = 25 mps t = 450 / 25 = 18 sec a ) 18 sec"
Answer: A