Abhi finishes a journey by car in 9 hours. He travels the first half of the journey at a speed of 40 km/h and the second half of the journey at a speed of 50 km/h. The total distance covered is:

400 km

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

= \(\frac{2 × 50  × 40  }{50 + 40}\)

= \(\frac{400  }{9}\)

Distance = Speed × Time

= \(\frac{400  }{9}\) × 9

= 400 km