Question

car moves with a speed of 30 km/Mr for half an hour, 25 km/h' for one hour and 40 km/h for two hours. Calculate average speed of the car

Answer 1

$\huge\boxed{Answer}$-------

In the first case , the car travels at a speed of 30km/hr for a time of 0.5 hour.

Now, Speed = $\frac{Distance}{Time}$

So ,

30 =$\frac{distance}{0.5}$

Therefore,

Distance

= 30 × 0.5

= 15km ..............(1)

In the second case , the car travels at a speed of 25km/hr for a time of 1 hour.

Since, Speed = $\frac{Distance}{Time}$

So ,

$25 = \frac{distance}{1}$

Therefore,

Distance

= 25 × 1

= 25km .............(2)

In the third case , the car travels at a speed of 40km/hr for a time of 2 hours.

Since ,

Speed = $\frac{Distance}{Time}$

So,

$40 = \frac{distance}{2}$

Therefore,

Distance

= 40 × 2

= 80km ...........(3)

By combining equations, (1),(2), and (3) , we get ...

Total Distance covered = 15 + 25 + 80
= 120 km.

Total time taken = 0.5 + 1 + 2
= 3.5 hours.

Therefore,

Average speed =

$\frac{Total\:distance\:travelled}{Total\:time\:taken}$

$= \frac{120}{3.5}$

$= 34.28$

Therefore ,
Average Speed = 34.28km/hr.

$\huge\mathcal{Be\:Brainly}$

Answer 2

Answer:

As we know that

average speed = total distance covered / total time taken

here, total speed is 30+25km/hr = 55 * 5/18 m/s

total time = 90 mins

so,average time = 15.27 / 90

=0.696

Explanation: