How many seconds will a train 120 meters long take to cross a bridge 150 meters long if the speed of the train is 36 kmph?  Pick one
A) 17 sec B) 21 sec C) 25 sec D) 27 sec E) 29 sec

Rationale: "d = 120 + 150 = 270 s = 36 * 5 / 18 = 10 mps t = 270 / 10 = 27 sec"
Answer: D