Question

Растояние между двумя причалами лодка проплывает по течению реки за 2 часа,а против течения - за 3 часа. Собственная скоро лодки равна 8 км/ч. найти расстояние между двумя причалами. найти скоро течения реки

Answer 1

Х- скорость реки
(8+х)*2=(8-х)*3
16+2х=24-3х
5х=8
х=1,6 (Км/час) - скорость течения реки
(8+1,6) х 2 = 19,2 (км) расстояние между двумя причалами. 

Answer 2

Calculation of Distance between Two Docks

To find the distance between two docks, we can use the formula:

Distance = Speed x Time

Let's denote the speed of the boat as B and the speed of the river current as C.

Given that the boat takes 2 hours to travel downstream (with the current) and 3 hours to travel upstream (against the current), and the boat's own speed is 8 km/h, we can set up the following equations:

Equation 1: Distance downstream = (B + C) x 2

Equation 2: Distance upstream = (B - C) x 3

To find the distance between the two docks, we need to solve these equations simultaneously.

Let's solve Equation 1 for the distance downstream:

Distance downstream = (B + C) x 2

Substituting the boat's speed (B = 8 km/h), we get:

Distance downstream = (8 + C) x 2

Similarly, let's solve Equation 2 for the distance upstream:

Distance upstream = (B - C) x 3

Substituting the boat's speed (B = 8 km/h), we get:

Distance upstream = (8 - C) x 3

Since the distance between the two docks is the same whether the boat is traveling upstream or downstream, we can equate the two distances:

(8 + C) x 2 = (8 - C) x 3

Now, let's solve this equation to find the value of C, which represents the speed of the river current.

Solving the Equation

Expanding the equation, we get:

16 + 2C = 24 - 3C

Combining like terms, we have:

5C = 8

Dividing both sides by 5, we find:

C = 8/5 = 1.6 km/h

Therefore, the speed of the river current is 1.6 km/h.

Calculating the Distance between the Two Docks

To find the distance between the two docks, we can substitute the value of C into either Equation 1 or Equation 2. Let's use Equation 1:

Distance downstream = (8 + C) x 2

Substituting C = 1.6 km/h, we get:

Distance downstream = (8 + 1.6) x 2 = 9.6 x 2 = 19.2 km

Therefore, the distance between the two docks is 19.2 km.

Summary

- The speed of the river current is 1.6 km/h. - The distance between the two docks is 19.2 km.

Please let me know if there's anything else I can help you with!