Question

Катер прошел расстояние между пристанями туда и обратно за 4.5 ч. Скорость течения реки 2 км/ч. Собственная скорость катера 18 км/ч. Найдите расстояние между пристанями.

Answer 1

Пусть х- расстояние от пристани и обратно, тогда 18-2=16 км/час скорость катера против течения и 18+2=20 км/час скорость катера по течению, составим уравнение:
$\frac{x}{16}+\frac{x}{20}=4,5$
$\frac{20x+16x}{16*20}=4,5$
$\frac{36x}{320}=4,5$
36х=4,5*350
36х=1440
х=1440:36
х=40 км расстояние между пристанями

Answer 2

Finding the Distance Between the Docks

To find the distance between the docks, we can use the formula: distance = speed × time.

First, let's find the speed of the boat relative to the water. The boat's speed in still water is 18 km/h, and the speed of the current is 2 km/h.

The boat's speed relative to the water is the difference between the boat's speed and the speed of the current: 18 km/h - 2 km/h = 16 km/h.

Now, we can use this speed to find the distance between the docks.

Calculating the Distance

The boat traveled the distance to the dock and back in a total of 4.5 hours. This means it spent half of that time, or 2.25 hours, traveling in each direction.

Using the formula distance = speed × time, we can calculate the distance between the docks for one leg of the journey: distance = speed × time = 16 km/h × 2.25 h = 36 km.

So, the distance between the docks is 36 kilometers.