Question

Катер шёл 2 часа по течению реки и 3 часа против течения. Всего он прошёл 148 км. Найдите собственную скорость катера,если скорость течения реки равна 2 км/ч

Answer 1

Пусть х скорость катера, тогда по течению 2(х+2), против 3(х-2)
2(х+2)+3(х-2)=148
2х+4+3х-6=148
5х-2=148
5х=148+2
5х=150
х=150:5
х=30 км/ч собственная скорость катера

Answer 2

Problem Analysis

We are given that a boat traveled for 2 hours with the current of a river and 3 hours against the current. The total distance traveled by the boat is 148 km, and the speed of the river current is 2 km/h. We need to find the speed of the boat.

Solution

Let's assume the speed of the boat is x km/h.

When the boat is traveling with the current, its effective speed is the sum of its own speed and the speed of the current. So, the effective speed is (x + 2) km/h. The boat traveled for 2 hours with this effective speed, covering a distance of 2(x + 2) km.

When the boat is traveling against the current, its effective speed is the difference between its own speed and the speed of the current. So, the effective speed is (x - 2) km/h. The boat traveled for 3 hours with this effective speed, covering a distance of 3(x - 2) km.

According to the given information, the total distance traveled by the boat is 148 km. Therefore, we can write the equation:

2(x + 2) + 3(x - 2) = 148

Simplifying the equation:

2x + 4 + 3x - 6 = 148

5x - 2 = 148

5x = 150

x = 30

Therefore, the speed of the boat is 30 km/h.

Answer

The speed of the boat is 30 km/h.