Question

A car covers first half of the total distance with speed of 36 km/ hr and the second half with a speed of 54 km / hr find the average speed of the car.

Answer 1

Their average speed is 43.2 km/hr.

Step-by-step explanation:

Given : A car cover first half of the total distance with speed 36 km/h and second half with speed of 54 km/h per hour.

To find : The average speed of the car?

Solution :

Let the distance covered in first half be x.

So second half distance will also be x.

We know,Time = Distance/speed

Time at first half is

t1 = x/36

Time at second half is

t2 = x/54

Average speed of the car is,

Average speed = Distance/speed

Average speed = 2x/3x+2x/10s

Average speed =2x×108/5x

Average speed =2×108/5

Average speed =43.2

Therefore, Their average speed is 43.2 km/hr.

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