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?\nOptions:\n(A) 4\n(B) 7\n(C) 6\n(D) 8\n(E) 9
Step-by-step reasoning process below:
(A)
S = 600/40 = 15 mps\nS = 3600/15 = 240 sec = 4 min.

The answer is (A)