Question

Из одного города в другой выехал поезд первую половину расстояния он проехал за 2,3 ч со скоростью 72,75км/ч а вторую половину за 3,6 .Найдите среднюю скорость поезда

Answer 1

2.3×72.75=167 км (1 половина)
167:3,6=46(  2 половина)
2,3+3,6=5,9 (время в пути)
167*2:2,3+3,6=148,6 (средняя)

Answer 2

Problem Analysis

We are given that a train traveled from one city to another. The train traveled the first half of the distance in 2.3 hours at a speed of 72.75 km/h, and the second half of the distance in 3.6 hours. We need to find the average speed of the train.

Solution

To find the average speed of the train, we can use the formula:

Average Speed = Total Distance / Total Time

Let's calculate the total distance and total time traveled by the train.

The time taken to travel the first half of the distance is 2.3 hours, and the speed is 72.75 km/h. Using the formula Distance = Speed × Time, we can calculate the distance traveled in the first half:

Distance1 = Speed1 × Time1

Distance1 = 72.75 km/h × 2.3 hours

The time taken to travel the second half of the distance is 3.6 hours. Using the same formula, we can calculate the distance traveled in the second half:

Distance2 = Speed2 × Time2

Distance2 = Speed2 × 3.6 hours

The total distance traveled by the train is the sum of the distances traveled in the first and second halves:

Total Distance = Distance1 + Distance2

The total time taken by the train is the sum of the times taken in the first and second halves:

Total Time = Time1 + Time2

Finally, we can calculate the average speed of the train using the formula mentioned earlier:

Average Speed = Total Distance / Total Time

Let's substitute the given values and calculate the average speed.

Calculation

Given: - Time1 = 2.3 hours - Speed1 = 72.75 km/h - Time2 = 3.6 hours

Using the formulas mentioned above, we can calculate:

Distance1 = 72.75 km/h × 2.3 hours

**Distance2 = Speed2 × 3.6 hours