A motor car drives at an average speed of 106km/h for 2 hours 45 minutes. At which constant speed must the car drive to travel the same distance in 2 hours 35 minutes ?
Let's start by finding the distance traveled by the car in the first scenario:
Distance = Speed × Time
We convert the time of 2 hours 45 minutes to hours by dividing 45 minutes by 60:
Time = 2 + 45/60 = 2.75 hours
Distance = 106 × 2.75 = 291.5 km
Now, let's find the speed required to travel the same distance in 2 hours 35 minutes. Again, we convert the time to hours:
Time = 2 + 35/60 = 2.583 hours
Distance = 291.5 km (same distance as before)
Speed = Distance ÷ Time
Speed = 291.5 ÷ 2.583
Speed ≈ 112.98 km/h
Therefore, the constant speed at which the car must drive to travel the same distance in 2 hours 35 minutes is approximately 112.98 km/h.