Question

A train ,100m long travelling at40m/s,starts overtaking another train 200m/s long travelling at 30m/s . The time taken by the first train to pass the second train completely is-
(A)30s. (B)40s
(C)50s. (D)60s

Answer 1

{c}50s is the answer

Answer 2

I think (b) is the answer.