Two cities, A and B, at a distance of 50 km, are connected by two separate roads. The speed of any vehicle traveling between the two cities on road 1 is 50 km/hr, while the speed on road 2 is (80/n) km/hr, where n is the number of vehicles (including the concerned vehicle). If you travel in a vehicle from A to B on road 1 and come back from B to A on road 2 (where there are already three vehicles plying), What is your approximate average speed ?
