Question

A motor car drives at an average speed of 106 km/h for 2 hours 45 minutes. At which constant speed must the car drive to travel the same distance in 2 hours 35 minutes?​

Answer 1

speed required = 113 km/h

Explanation:

The question tells us that a car travels at an average speed of 106 km/h for 2 hours and 45 minutes. It then asks us to calculate the constant speed the vehicle would need to drive at to travel the same distance in 2 hours and 35 minutes.

To solve this, we must first find the distance travelled by the car in 2 hours and 45 minutes. But before that, let's convert 2 hours and 45 minutes into hours:

2 hours 45 minutes =
`\mathrm{2 +(45 )/(60) }`

= 2.75 h

Now, let's calculate the distance:

distance = speed × time

= 106 × 2.75

= 291.5 km

Now that we know the distance travelled by the car, we can easily calculate the speed it would need to cover it in 2 hours and 35 minutes (2.58 h):

speed = distance ÷ time

= 291.5 ÷ 2.58

= 112.98 km/h

`\approx` 113 km/h

Therefore, the car must drive at a constant speed of approximately 113 km/h to travel the same distance in 2 hours 35 minutes.