A train is running at the speed of 70 km/hr from A to B at 11 am. At the same time another train is running from B to A at the speed of 90 km/hr. If they are running on parallel tracks and the distance between two stations is 480 km, then at what time will they start to cross each other?

2:00 pm

Distance b/w two station = 480 km

Relative speed in opposite direction = 70 + 90 = 160 km/hr

Time = \(\frac{distance}{relative\;speed}\) = \(\frac{480}{160}\) = 3 hours

Train will start to cross each other at = 11:00 am + 3 hours = 2:00 pm