Question

A car travels along straight line for first half time with a speed of 40 km/h and the second half with a speed of 60km/h find the average speed of the car ??

Answer 1

Average speed of car will be 48 km/hr

Step-by-step explanation:

Let the total distance is 2d

It is given that first half of the distance car travels with a speed of 40 km/hr

So time taken to cover half of the distance
`t_1=(d)/(40)hr`

Second half of the distance is covered with a 60 km/hr

So time taken to cover second half of the distance
`t_2=(d)/(60)hr`

So total time to cover 2d distance
`t=(d)/(60)+(d)/(40)=(5d)/(120)`

Average speed is the ratio of total distance to total time

So average speed
`=(2d)/((5d)/(120))=48km/hr`

So average speed of car will be 48 km/hr