Question

Катер шёл по реке 3 часа со скоростью 24 км/ч, а затем по озеру 4 часа со скоростью 21 км/ч. Найдите путь, пройденный катером и скорость течения.

Answer 1

1)24-21=3(км/ч)-скорость течения реки                                                                  2)3*24=72(км)-прошёл по реке                                                                             3)4*21=84(км)-прошёл по озеру                                                                            4)72+84=156(км)

Answer 2

Calculation of Distance and Current Speed

To find the distance traveled by the boat and the speed of the current, we can use the formula:

Distance = Speed x Time

Let's calculate the distance traveled by the boat on the river and the lake separately.

1. Distance traveled on the river: - Time = 3 hours - Speed = 24 km/h - Distance = Speed x Time = 24 km/h x 3 hours = 72 km

2. Distance traveled on the lake: - Time = 4 hours - Speed = 21 km/h - Distance = Speed x Time = 21 km/h x 4 hours = 84 km

Therefore, the total distance traveled by the boat is 72 km on the river and 84 km on the lake.

To find the speed of the current, we can compare the boat's actual speed on the river and the lake with its effective speed (relative to the ground) during those times.

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

1. On the river: - Boat's speed = 24 km/h - Effective speed (relative to the ground) = Boat's speed - Speed of the current = 24 km/h - x km/h

2. On the lake: - Boat's speed = 21 km/h - Effective speed (relative to the ground) = Boat's speed - Speed of the current = 21 km/h - x km/h

Since the boat's effective speed on the river and the lake remains constant, we can equate the two expressions:

24 km/h - x km/h = 21 km/h - x km/h

Simplifying the equation, we find:

24 - x = 21 - x

The speed of the current (x) cancels out, indicating that the speed of the current does not affect the boat's effective speed.

Therefore, the speed of the current cannot be determined based on the given information.

To summarize: - The boat traveled a total distance of 72 km on the river and 84 km on the lake. - The speed of the current cannot be determined based on the given information.

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