Question

От причала вниз по реке отплыл плот.Ниже по течению реки на расстоянии 17 км от первого причала находится второй причал.От него навстречу плоту через 2/3 часа после отплытия плота отправляется теплоход.Собственная скорость теплохода равна 25км\ч,а скорость течения реки равна 3 км\ч.Через какое время после своего отплытия плот встретится с теплоходом?

Answer 1

)3*2:3=2КМ-ПРОПЛЫЛ ПЛОТ ЗА 2/3ЧАСА.

2)17-2=15КМ-РАССТОЯНИЕ МЕЖДУ ПЛОТОМ И ТЕПЛОХОДОМ В МОМЕНТ ЕГО ОТПРАВЛЕНИЯ.

3)25-3=22КМ/Ч-СКОРОСТЬ ТЕПЛОХОДА ПРОТИВ ТЕЧЕНИЯ.

4)15:(3+22)=15/25=ЧЕРЕЗ 3/5ЧАСА-ВСТРЕТЯТСЯ ПОСЛЕ ОТПЛЫТИЯ ТЕПЛОХОДА.

5)3/5+2/3=(9+10):15=19/15=1 16/60=ЧЕРЕЗ 1Ч 16МИН(76МИН)-ВСТРЕТЯТСЯ ПОСЛЕ ОТПЛЫТИЯ ПЛОТА.

Answer 2

Problem Analysis

We are given the following information: - A raft departs from the first dock and travels downstream on a river. - The second dock is located 17 km downstream from the first dock. - A steamboat departs from the second dock and travels upstream towards the raft. - The steamboat departs 2/3 of an hour after the raft.

We need to determine how long it will take for the raft and the steamboat to meet.

Solution

To solve this problem, we can use the concept of relative speed. The relative speed between the raft and the steamboat is the sum of their individual speeds.

Let's calculate the speed of the raft first. Since it is traveling downstream, its speed will be the sum of its own speed and the speed of the river current. Given that the speed of the river current is 3 km/h, we can calculate the speed of the raft as follows:

Speed of the raft = Speed of the raft + Speed of the river current = 0 km/h + 3 km/h = 3 km/h

Next, let's calculate the speed of the steamboat. Since it is traveling upstream, its speed will be the difference between its own speed and the speed of the river current. Given that the speed of the steamboat is 25 km/h and the speed of the river current is 3 km/h, we can calculate the speed of the steamboat as follows:

Speed of the steamboat = Speed of the steamboat - Speed of the river current = 25 km/h - 3 km/h = 22 km/h

Now, we can calculate the time it will take for the raft and the steamboat to meet. We can use the formula:

Time = Distance / Relative Speed

The distance between the first and second docks is 17 km. The relative speed is the sum of the speeds of the raft and the steamboat, which is 3 km/h + 22 km/h = 25 km/h. Substituting these values into the formula, we get:

Time = 17 km / 25 km/h = 0.68 hours

Therefore, it will take approximately 0.68 hours for the raft and the steamboat to meet.

Answer

The raft and the steamboat will meet approximately 0.68 hours after the raft departs from the first dock.

Note: The information provided in the question is incomplete and does not provide enough context to determine the exact location or names of the docks, or the specific date and time of departure. Therefore, the answer is based on the given information and assumptions made for the solution.