Question

a journey by a car takes 48 minutes at 65 km per hour how fast must be the car go to finish the journey in 40 minutes​

Answer 1

Answer:

The car must go at a speed of 78

kmph to finish the journey in 40

minutes.

Step-by-step explanation:

It is given that: a car takes 48

minutes time to complete a journey when the speed is 65

kmph.

We have to find the speed of the car when the same journey has to finish within 40

minutes.

At first, we will find the distance of the journey.

We know that, if a car travels with speed v and completes a journey in t time, its distance will be v×t

.

Substitute the value of v=65,t=48

we get,

The distance the car travelled is =65×4860

kmpm (kilometre per minute)

Here we divide it with 60 for converting the distance per hour to distance per minute. Because it is given the distance in an hour but we have to calculate the distance in minutes. Therefore we convert the distance of time.

On simplifying the above equation we get the distance covered by the car,

The distance travelled by the car is 52

km

Now, the car has to cover 52

km within 40

minutes.

So, let us substitute the distance and time in the speed formula we get,

Speed=5240×60

kmph (kilometre per hour)

By calculating the above calculation of multiplication and division we get, the speed as 78

kmph.