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?\nOptions:\n(A) 29\n(B) 18\n(C) 48\n(D) 99\n(E) 11
Stream of thoughts:
(C)
D = 540 + 180 = 720\nS = 54 * 5/18 = 15 mps\nT = 720/15 = 48 se.

So, the final answer is (C)