Question

Поезд прошел 485 км. Первые 2 ч. поезд шёл со скоростью 55 км/ч, а потом -- со скоростью 75 км/ч. Сколько времени поезд затратил на весь путь?

Answer 1

1)55*2=110км прошел поезд за первые 2 часа
2)485-110=375км прошел поезд потом
3)375/75=5 часов 
4)5+2=7 часов время всей поездки
Ответ:7 часов время всей поездки

Answer 2

2*55=110(км)- прошёл за 2 часа
485-110=375(км)- прошёл со скоростью 75 км/ч
375:75=5(ч.)- шёл со скоростью 75 км/ч
2+5=7(ч.)- поезд затратил на весь путь

Answer 3

Calculation of Time Taken by the Train

To calculate the time taken by the train to cover the entire distance, we need to consider the two different speeds at which the train traveled.

The train traveled a total distance of 485 km. In the first 2 hours, the train traveled at a speed of 55 km/h, and then it traveled at a speed of 75 km/h.

To calculate the time taken for the first part of the journey, we can use the formula:

Time = Distance / Speed

For the first part of the journey, the distance covered is 55 km/h * 2 h = 110 km.

Therefore, the time taken for the first part of the journey is:

Time1 = 110 km / 55 km/h = 2 hours

To calculate the time taken for the second part of the journey, we can use the same formula:

Time2 = Distance / Speed

For the second part of the journey, the distance covered is 485 km - 110 km = 375 km.

Therefore, the time taken for the second part of the journey is:

Time2 = 375 km / 75 km/h = 5 hours

Finally, to calculate the total time taken for the entire journey, we add the times for the first and second parts:

Total Time = Time1 + Time2 = 2 hours + 5 hours = 7 hours

Therefore, the train took a total of 7 hours to cover the entire distance of 485 km.

Please note that the calculations are based on the given information and assume a constant speed throughout each part of the journey.