Question

В течении двух часов пояс двигался со скоростью 110 км/ч, затем сделал остановку на 10 минут. Оставшуюся часть он шёл со скоростью 90 км/ч. Какова средняя скорость поезда на всем пути, если он прошел 400 км?

Answer 1

1) 111 * 2 = 220 км2) 400- 220 = 180 км3) 180 / 90 = 2 часа4) 2 + 2 + 1/6 = 25/6 часов (всего в пути)5) Vср = Sвсе / Tвсе    Vср = 400 / (25/6) = 96 км/ч 

Answer 2

Calculating the Average Speed of the Train

To calculate the average speed of the train for the entire journey, we can use the formula:

Average Speed = Total Distance / Total Time

First, let's calculate the total time taken for the journey.

The train traveled at a speed of 110 km/h for a certain time, then stopped for 10 minutes, and finally traveled at a speed of 90 km/h for the remaining time.

Calculating the Total Time Taken

The time taken at 110 km/h can be calculated using the formula:

Time = Distance / Speed

The time taken at 90 km/h can also be calculated using the same formula.

Let's calculate the total time taken for the journey.

Calculating the Total Distance

The total distance traveled by the train is given as 400 km.

Now, let's calculate the total time taken and then use it to find the average speed of the train for the entire journey.

Solution

The total time taken for the journey can be calculated as follows:

1. Time taken at 110 km/h: - Time1 = Distance / Speed = 400 km / 110 km/h = 3.636 hours

2. Time taken at 90 km/h: - Time2 = Distance / Speed = 400 km / 90 km/h = 4.444 hours

Total time taken = Time1 + Time2 + 10 minutes (converted to hours) = 3.636 hours + 4.444 hours + (10 minutes / 60) hours = 8.28 hours

Now, we can calculate the average speed of the train for the entire journey using the formula:

Average Speed = Total Distance / Total Time

Average Speed = 400 km / 8.28 hours = 48.31 km/h

Therefore, the average speed of the train for the entire journey, considering the stop, is 48.31 km/h.