A train 210 meters long is running with a speed of 54 kmph. The time taken by it to cross a tunnel 120 meters long is?
Options:
(A) 29
(B) 22
(C) 48
(D) 99
(E) 11 OK. Let's think. Some random thoughts first:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
D = 210 + 120 = 330
S = 54 * 5/18 = 15 mps
T = 330/15 = 22 sec The answer: (B).