Question

Из аэропорта с интервалом в 1 ч по одному и тому же маршруту вылетели два самолёта.Средняя скорость первого самолёта 900 км/ч,а расстояние, которое он должен преодолеть,-1800км.С какой средней скоростью летел второй самолёт, если он приземлился на 40 мин позже, чем первый?

Answer 1

Вылетели
1самолет=9.00утра
2самолет=на час позже
Скорость 1самолета= 900км/ч
Скорость 2самолета=? Км/ч
Расстояние =1800км
2самолет приземлился на 40мин позже

1)) 9ч00мин+1ч=10ч утра вылетел 2 самолет

2)) 1800:900=2ч летел 1 самолет

3)) 9ч00+2ч=11ч приземлился 1 самолет

4)) 11ч00+40мин= 11ч40мин приземлился 2 самолет

5)) 11ч 40мин - 10ч00мин= 1ч 40мин летел 2 самолет

Переводим в дробь
1ч=60мин;
1ч 40мин= 1 40/60ч = 1 2/3часа

6)) 1800 :1 2/3= 1800: (1•3+2)/3=
1800: 5/3= 1800• 3/5=
360•3/1= 1080км/ч скорость второго самолёта

Или без дроби так 6))
1ч=60мин
1ч40мин=60+40=100мин
1800км: 100мин= 18км/мин скорость
2 самолета
18км/мин• 60мин= 1080 км/час скорость 2 самолета

Ответ: второй самолёт летел со средней скоростью 1080 км/час

Answer 2

Problem Analysis

We are given that two planes took off from the same airport with a 1-hour interval on the same route. The first plane has an average speed of 900 km/h and needs to cover a distance of 1800 km. The second plane landed 40 minutes later than the first plane. We need to find the average speed of the second plane.

Solution

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

Average Speed = Total Distance / Total Time

Let's calculate the total time for the first plane:

Total Time = Time taken by the first plane + 1 hour

The time taken by the first plane can be calculated using the formula:

Time taken = Distance / Speed

Substituting the given values:

Time taken by the first plane = 1800 km / 900 km/h = 2 hours

Therefore, the total time for the first plane is:

Total Time = 2 hours + 1 hour = 3 hours

Now, let's calculate the time taken by the second plane. We know that the second plane landed 40 minutes (or 2/3 hours) later than the first plane. Therefore, the time taken by the second plane is:

Time taken by the second plane = Total Time - 2/3 hours

Substituting the value of the total time:

Time taken by the second plane = 3 hours - 2/3 hours = 8/3 hours

Finally, we can calculate the average speed of the second plane using the formula:

Average Speed = Distance / Time taken by the second plane

Substituting the given distance and the calculated time:

Average Speed = 1800 km / (8/3) hours

Simplifying the expression:

Average Speed = 1800 km * (3/8) hours = 675 km/h

Therefore, the average speed of the second plane is 675 km/h.

Answer

The second plane flew with an average speed of 675 km/h.