A train is running at the speed of 30 km/hr from A to B at 8 am. At the same time another train is running from B to A at the speed of 40 km/hr. If they are running on parallel tracks and the distance between two stations is 350 km, then at what time will they start to cross each other?

1:00 pm

Distance b/w two station = 350 km

Relative speed in opposite direction = 30 + 40 = 70 km/hr

Time = \(\frac{distance}{relative\;speed}\) = \(\frac{350}{70}\) = 5 hours

Train will start to cross each other at = 8 + 5 = 1:00 pm