A motorcycle covers 50 km at a speed of 25 km/h. Find the speed of the motorcycle for the next 50 km of the journey so that the average speed of the whole journey will be 30 km/h.

37.5 km/h

As distance is same .

So ,

Average Speed = \(\frac{2 × S1 × S2 }{S1 + S2}\)

30 = \(\frac{2 × 25 × S2 }{25 + S2}\)

30 = \(\frac{50 × S2 }{25 + S2}\)

750 + 30 S2 = 50 S2

20 S2 = 750

S2 = 37.5 km/h

So , Speed of motorcycle is 37.5 km/h