A car covers the first 39 kms of its journey in 45 minutes and covers the remaining 25 km in 35 minutes. What is the average speed of the car ?

Answer: Option B

Total distance travelled :
= (39 + 25) km
= 64 km
Total time taken
= (45 + 35) min
= 80 min
= $$\frac{4}{3}$$ hr
∴ Average speed :
= $$\left(64\times \frac{3}{4}\right)$$  km/hr
= 48 km/hr