Question: A 600 meter long train crosses a signal post in 40 seconds. How long will it take to cross a 3 kilometer long bridge, at the same speed?
Options:
(A) 4 min
(B) 5 min
(C) 6 min
(D) 8 min
(E) 10 min Random thoughts:

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
S = 600/40 = 15 mps
S = 3600/15 = 240 sec = 4 min The final answer: (A).