In how much time will a train running at a speed of 48 km/hr cross the other train running in opposite direction?
I. The length of the two trains is 90 metres and 120 metres respectively.
II. The speed of the second train is 60 km/hr.
From I, Distance = 120 + 90 = 210 m. From II, and the question, Relative speed = 48 + 60 = 108 km/hr. ∴ Time = (210 ×18)/(108 × 5) = 7 sec. Therefore, both the statement I and II together are required to answer the question.