Question

Моторная лодка проплыла 18 км по течению и 14 км против течения. На всю дорогу потрачено 3 часа 15 мин. Скорость лодки 10 км/час. Найдите скорость течения.

Answer 1

15 минут - 0,25 часа.
Все время 3,25 часа.
Пускай х-скорость течения.
18/10+х  время по течению реки.
14/10-х   время против течения реки.
Составляем уравнение:
18/10+х + 14/10-х = 3,25
Делаем его( после упрощений получится квадратное).
Берешь только положительный корень, так как скорость не может иметь знак -

Answer 2

Calculating the Current Speed of the Boat and the River

To find the speed of the river's current, we can use the formula: Speed of the boat in still water = (Speed downstream + Speed upstream) / 2 Speed of the current = (Speed downstream - Speed upstream) / 2

Given: - Distance downstream = 18 km - Distance upstream = 14 km - Total time = 3 hours 15 minutes = 3.25 hours - Speed of the boat = 10 km/h

First, let's calculate the speed downstream and upstream: - Speed downstream = Distance downstream / Time downstream - Speed upstream = Distance upstream / Time upstream

Calculating Speed Downstream

- Speed downstream = 18 km / (3.25 hours - Time upstream)

Calculating Speed Upstream

- Speed upstream = 14 km / (3.25 hours - Time downstream)

Now, we can use the formulas to find the speed of the river's current.

Calculating Speed of the River's Current

- Speed of the boat in still water = (Speed downstream + Speed upstream) / 2 - Speed of the current = (Speed downstream - Speed upstream) / 2

Let's calculate the speed of the river's current using the given information and the formulas above.