Question

252. Автомобіль проїхав першу частину шляху за 2,6 год зі швидкістю 78 км/год, а другу частину - за 3,9 год. З якою швидкістю автомобіль проїхав другу частину шляху, якщо середня швидкість протягом усього часу руху становила 70,2 км/год?​

Answer 1

Ответ:

будет примерно 16 кьадлаткд

Answer 2

Calculation of the Second Part of the Distance

To find the speed at which the car traveled the second part of the distance, we need to calculate the distance traveled in each part of the journey.

Let's assume the total distance is D km.

The first part of the journey took 2.6 hours at a speed of 78 km/h. Therefore, the distance traveled in the first part is:

Distance of the first part = Speed of the first part × Time of the first part = 78 km/h × 2.6 hours = 202.8 km.

The second part of the journey took 3.9 hours. To find the distance traveled in the second part, we subtract the distance of the first part from the total distance:

Distance of the second part = Total distance - Distance of the first part = D km - 202.8 km.

Calculation of the Average Speed

The average speed for the entire journey is given as 70.2 km/h. We can use this information to find the total distance:

Average speed = Total distance / Total time.

The total time is the sum of the time taken for the first and second parts of the journey:

Total time = Time of the first part + Time of the second part = 2.6 hours + 3.9 hours = 6.5 hours.

Substituting the values into the average speed equation:

70.2 km/h = Total distance / 6.5 hours.

Solving for the total distance:

Total distance = 70.2 km/h × 6.5 hours = 455.3 km.

Calculation of the Speed for the Second Part

Now that we know the total distance and the distance of the first part, we can find the distance of the second part:

Distance of the second part = Total distance - Distance of the first part = 455.3 km - 202.8 km = 252.5 km.

To find the speed at which the car traveled the second part, we divide the distance of the second part by the time taken for the second part:

Speed of the second part = Distance of the second part / Time of the second part = 252.5 km / 3.9 hours ≈ 64.74 km/h.

Therefore, the car traveled the second part of the distance at a speed of approximately 64.74 km/h.

Please note that the calculations are based on the information provided and may vary slightly depending on the exact values used.