Question

Из Санкт-Петербурга в Москву Вышел товарный поезд со скоростью 48 км/ч, а через час после этого из москвы в Санкт-Петербург вышел скорый поезд со скоростью 82км/ч. Найдите растояние между поездами: а) через один час после выхода скорого поезда,б)через 3 часа после выхода товарного поезда,в)через 5 ч после выхода скоростного поезда.Расстояние от Москвы до Санкт-Петербурга 650 км.

Answer 1

1)2*48=96 км/ч-расстояние товарного 
-96+82=178 
-650-178=472(км)          ЭТО ЧЕРЕЗ ЧАС

2)3*48=144 расст. товарного 
 2*82=164 расст. скорого 
 144+164=30 общее расстояние 
 650-308=342(км) расст. между поездами       ЭТО ЧЕРЕЗ 3 ЧАСА

3)6*48=288 расст. товарного 
 5*82=410 расст. скорого 
 288+410=698 общее расстояние 

 698-650=48(км) расст. между поездами     ЧЕРЕЗ 5  ЧАСОВ

Answer 2

650-48=602(км)-расстояние между поездами во время выхода скорого поезда

602-48-82=472(км)-расст через час

 

650-48*3-82*2=342(км)-через 3 ч после выхода товарного

 

5*82=410(км)-проехал скорый за 5 ч

6*48=288(км)-проехал тов за 6 ч

650-410=240(км)-осталочь проехать скорому

288-240=48(км)-расстояние между поездами через 5 ч после выхода скорого п 

 

Answer 3

Calculation of Distances

To calculate the distances between the trains, we need to consider their speeds and the time that has passed since they departed. Let's calculate the distances for each scenario:

a) One hour after the express train departs:

- The freight train has been traveling for one hour at a speed of 48 km/h. - The express train has just departed from Moscow and is traveling at a speed of 82 km/h.

To calculate the distance between the two trains, we need to find the distance traveled by each train in one hour.

- Distance traveled by the freight train in one hour: 48 km/h * 1 h = 48 km. - Distance traveled by the express train in one hour: 82 km/h * 1 h = 82 km.

The distance between the two trains after one hour is the sum of the distances traveled by each train: 48 km + 82 km = 130 km.

b) Three hours after the freight train departs:

- The freight train has been traveling for three hours at a speed of 48 km/h. - The express train has been traveling for two hours at a speed of 82 km/h.

To calculate the distance between the two trains, we need to find the distance traveled by each train in three hours.

- Distance traveled by the freight train in three hours: 48 km/h * 3 h = 144 km. - Distance traveled by the express train in two hours: 82 km/h * 2 h = 164 km.

The distance between the two trains after three hours is the difference between the distance traveled by the express train and the distance traveled by the freight train: 164 km - 144 km = 20 km.

c) Five hours after the express train departs:

- The freight train has been traveling for six hours at a speed of 48 km/h. - The express train has been traveling for five hours at a speed of 82 km/h.

To calculate the distance between the two trains, we need to find the distance traveled by each train in five hours.

- Distance traveled by the freight train in six hours: 48 km/h * 6 h = 288 km. - Distance traveled by the express train in five hours: 82 km/h * 5 h = 410 km.

The distance between the two trains after five hours is the difference between the distance traveled by the express train and the distance traveled by the freight train: 410 km - 288 km = 122 km.

Therefore, the distances between the trains are as follows: a) One hour after the express train departs: 130 km. b) Three hours after the freight train departs: 20 km. c) Five hours after the express train departs: 122 km.

Please note that these calculations assume constant speeds for the trains and do not take into account any stops or changes in speed that may occur during the journey.