Question

Akhil drove his car with speed of 20km/h while going to his college when he returned to his home along the same route the speed of the car is 30km/h calculate the average speed of the car during entire the journey

Answer 1

Let distance be d
Speed (1) = 20km/h
Time taken = distance / speed
= d/20
Speed (2) = 30km/h
Time = Distance/time
= d/30
Average speed = total distance /total time
=( d+d) /{(d/20)+(d/30)}
= 2d / (d/12)
=24d/ d
= 24


So, the average speed of the car was 24km/h

Answer 2

Given,

Speed of the car=20km/hr

At the time of return back speed of the car=30km/hr

To Find,

The average speed of the car.

Solution,

Let distance be d from home to college

So, speed x = 20km/h

Time taken for x distance = distance / speed

= d/20

Also for speed, y = 30km/h

Time taken for y distance= Distance/time

= d/30

So here, Average speed = total distance /total time

=( d+d) /((d/20)+(d/30))

= 2d / (d/12)

=24d/ d

= 24km/hr

Hence, average speed of the car is 24km/hr.