Question

Из двух городов одновременно навстречу друг другу отправились скорый т товарный поезда.Они встретились через 9 ч.Какое расстояние между городами,если известно,что скорость поезда 80км ч,а скорость товарного поезда составляет половину от его скорости ?

Answer 1

80/2=40 км/ч скорость товарного поезда
(80 км/ч+ 40 км/ч)*9 ч=1080 км расстояние между городами

Answer 2

Problem Analysis

We are given that a fast passenger train and a freight train started simultaneously from two cities and met each other after 9 hours. We need to find the distance between the cities given that the speed of the passenger train is 80 km/h and the speed of the freight train is half of the passenger train's speed.

Solution

Let's assume the distance between the two cities is D km.

We know that the time taken by both trains to meet is 9 hours.

The formula to calculate the distance is:

Distance = Speed × Time

For the passenger train: Distance covered by the passenger train = Speed of the passenger train × Time taken by both trains to meet

For the freight train: Distance covered by the freight train = Speed of the freight train × Time taken by both trains to meet

Since the speed of the freight train is half of the passenger train's speed, we can write:

Distance covered by the freight train = (1/2) × Speed of the passenger train × Time taken by both trains to meet

The total distance covered by both trains is equal to the distance between the cities:

Distance covered by the passenger train + Distance covered by the freight train = Distance between the cities

Substituting the values:

Speed of the passenger train × Time taken by both trains to meet + (1/2) × Speed of the passenger train × Time taken by both trains to meet = Distance between the cities

Simplifying the equation:

(1 + 1/2) × Speed of the passenger train × Time taken by both trains to meet = Distance between the cities

(3/2) × Speed of the passenger train × Time taken by both trains to meet = Distance between the cities

Substituting the given values:

(3/2) × 80 km/h × 9 hours = Distance between the cities

Calculating the distance:

(3/2) × 80 km/h × 9 hours = 360 km

Therefore, the distance between the two cities is 360 km.

Answer

The distance between the two cities is 360 km.