Student: A train 540 meters long is running with a speed of 54 kmph. The time taken by it to cross a tunnel 180 meters long is?
Options:
(A) 17 sec
(B) 14 sec
(C) 48 sec
(D) 87 sec
(E) 25 sec.
Another student: Let's say, hmmm...

user
D = 540 + 180 = 720
S = 54 * 5/18 = 15 mps
T = 720/15 = 48 se Final answer: (C).
assistant