Question

Даю 90баллов 4Задача Расстояние между двумя пунктами моторная лодка прошла по течению реки за 5часов,а против течения за 6часов.Найдите собственную скорость лодки между этими пунктами,если скорость течения реки 3км/ч​

Answer 1

Ответ:

33 км/ч.

Пошаговое объяснение:

Пусть собственная скорость лодки х км/ч, тогда её скорость по течению х+3 км/ч, против течения х-3 км/ч. Составим уравнение:

5(х+3) = 6(х-3)

5х+15=6х-18

х=33

Answer 2

ответ:

5*(х+3)=6*(х-3)

х= 33

надеюсь помогла)

Answer 3

Problem Analysis

We are given that a motorboat traveled a certain distance in 5 hours with the current of the river and in 6 hours against the current. We need to find the speed of the boat in still water.

Solution

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

When the boat is traveling with the current, its effective speed is the sum of its speed in still water and the speed of the current. So, the effective speed is (x + 3) km/h.

When the boat is traveling against the current, its effective speed is the difference between its speed in still water and the speed of the current. So, the effective speed is (x - 3) km/h.

We can use the formula distance = speed × time to calculate the distance traveled in both cases.

1. When traveling with the current: - Speed = (x + 3) km/h - Time = 5 hours - Distance = (x + 3) × 5 km

2. When traveling against the current: - Speed = (x - 3) km/h - Time = 6 hours - Distance = (x - 3) × 6 km

Since the distance traveled in both cases is the same, we can set up the following equation:

(x + 3) × 5 = (x - 3) × 6

Now, let's solve this equation to find the value of x.

Calculation

Expanding the equation:

5x + 15 = 6x - 18

Rearranging the terms:

6x - 5x = 15 + 18

Simplifying:

x = 33

Answer

The speed of the boat in still water is 33 km/h.

Explanation

When the boat is traveling with the current, its speed is 33 km/h + 3 km/h (current speed) = 36 km/h. In 5 hours, it covers a distance of 36 km/h × 5 hours = 180 km.

When the boat is traveling against the current, its speed is 33 km/h - 3 km/h (current speed) = 30 km/h. In 6 hours, it covers a distance of 30 km/h × 6 hours = 180 km.

Therefore, the distance traveled in both cases is the same, confirming that the speed of the boat in still water is indeed 33 km/h.