Question

Расстояние между двумя городами 385 км. Из этих городов одновременно в противоположных направлениях, удаляясь друг от друга,вышли два поезда. Скорость одного 65 км/ч, скорость второго составляет 4/5 скорости первого. Найди расстояние между поездами через 3 ч после начала движения

Answer 1

65/5*4 = 52 км/час - скорость второго поезда
52+65 = 117 км/час - общая скорость
117*3 = 351 км пройдут поезда за 3 часа
351+385 = 736 км было между поездами через 3 часа движения

Answer 2

1) скорость второго поезда
65*4/5=52км/ч
2) за 3 часа первый поезд пройдет
65*3=195 км
3) за 3 часа второй поезд пройдет
52*3=156 км
4) через 3 часа расстояние между поездами будет
195+385+156=736км

Answer 3

Problem Analysis

We are given that two trains start simultaneously from two cities, moving away from each other in opposite directions. The speed of one train is 65 km/h, and the speed of the other train is 4/5 times the speed of the first train. We need to find the distance between the trains after 3 hours of travel.

Solution

To find the distance between the trains after 3 hours, we need to calculate the total distance covered by both trains in 3 hours.

Let's denote the speed of the first train as V1 and the speed of the second train as V2.

Given: - Speed of the first train, V1 = 65 km/h - Speed of the second train, V2 = 4/5 * V1

To find the distance covered by each train in 3 hours, we can use the formula:

Distance = Speed * Time

For the first train: Distance1 = V1 * 3

For the second train: Distance2 = V2 * 3

To find the total distance between the trains, we can add the distances covered by each train:

Total Distance = Distance1 + Distance2

Let's calculate the values:

V2 = 4/5 * 65 km/h = 52 km/h

Distance1 = V1 * 3 = 65 km/h * 3 = 195 km

Distance2 = V2 * 3 = 52 km/h * 3 = 156 km

Total Distance = Distance1 + Distance2 = 195 km + 156 km = 351 km

Therefore, the distance between the trains after 3 hours of travel is 351 km.

Answer

The distance between the two cities is 385 km. After 3 hours of travel, the distance between the trains is 351 km.