Question

Лодка шла по течению реки со скоростью 12км/ч, а против течения-со скоростью 8км/ч. Какова скорость течения реки?

Answer 1

12-8=4 вот ответ
!!!!!!!

Answer 2

Calculation of the River's Current Speed

To determine the speed of the river's current, we can use the given information about the boat's speed both with and against the current.

Let's assume that the speed of the river's current is represented by x km/h.

When the boat is moving with the current, its speed is 12 km/h. This means that the boat's speed relative to the ground is the sum of its speed with the current and the speed of the current itself. Therefore, we can write the equation:

12 km/h = boat's speed with the current + x km/h.

Similarly, when the boat is moving against the current, its speed is 8 km/h. In this case, the boat's speed relative to the ground is the difference between its speed against the current and the speed of the current. We can write the equation:

8 km/h = boat's speed against the current - x km/h.

To find the speed of the current, we can solve these two equations simultaneously.

Solving the Equations

Let's solve the equations using algebraic methods:

1. From the first equation, we can isolate the boat's speed with the current:

boat's speed with the current = 12 km/h - x km/h.

2. From the second equation, we can isolate the boat's speed against the current:

boat's speed against the current = 8 km/h + x km/h.

3. Now, we can substitute these expressions into the equation:

12 km/h - x km/h = 8 km/h + x km/h.

4. Simplifying the equation, we get:

4 km/h = 2x km/h.

5. Dividing both sides of the equation by 2, we find:

2 km/h = x km/h.

Answer

Therefore, the speed of the river's current is 2 km/h.

Please note that this calculation assumes a constant speed of the river's current and does not take into account other factors that may affect the actual speed of the current.