A car travels 80 km at the speed of 20 km/h and the next 30 km at the speed of 30 km/h. What is the average speed?

Correct option is D

Given:
First time
Speed = 20 km/h
Distance = 80 km
For next 30 km
Speed = 30 km/h
Formula Used:
Speed = $$\frac{\text{Distance}}{\text{Time}}$$​​
Solution:
For first 80 km
Total time taken to cover the distance
=> Time =$$\frac{\text{Distance}}{\text{Time}}= \frac{80}{20}= 4 h$$​​
Now for next 30 km
=> Time taken = $$\frac{30}{30}$$= 1 hr​
=> Total distance covered = 80 + 30 = 110 km
=> Total time = 5 h
=> Average speed of car = $$\frac{\text{Total Distance}}{\text{Total Time}} = \frac{110}{5} = 22 \, \text{km/h}$$​​
=> Hence, Average speed of car is 22 km/h