A 1200 m long train crosses a tree in 120 sec, how much time will I take to pass a platform 400 m long?	Choose the correct choice
A) 176 sec B) 190 sec C) 178 sec D) 160 sec E) 276 sec

Rationale: "l = s * t s = 1200 / 120 s = 10 m / sec . total length ( d ) = 1600 m t = d / s t = 1600 / 10 t = 160 sec answer : d"
Answer: D