The distance between P and Q is 720 km. A train leaves P at 6 am and runs at a speed of 20 m/s. The train stops on the way for 1 hour 30 minutes. At what time train will reach at Q?

5 : 30 pm

Given :-

Distance = 720 km

Speed = 20 m/sec

20 m/sec = 20 × \(\frac{18}{5}\) = 72 km/h

Time taken = \(\frac{Distance}{Speed}\)

= \(\frac{720}{72}\) = 10 hours

Trains start at 6:00 am . So , train reach  Q at = 6:00 am + 10 hours + 1 hour 30 minutes

= 5:30 pm