Question

Рыболов проплыл на лодке от пристани некоторе расстояние вверх по течению реки, затем бросил якорь, 2 часа ловил рыбу и вернулся обратно через 5 часов от начала путешествия. На какое расстояние от пристани он отплыл, если скорость течения реки равна 4км/ч, а собственная скорость лодки 6 км/ч?

Answer 1

Расстояние равно Х, тогда

х/(6-4) - время против течения

х/(6+4)- время на обратный путь

Туда, обратно и остановка на 2 часа составили 5 часов или :

(х/2+)(х/10)+2=5

0,5х+0,1х+2=5

0,6х=3

х=5км расстояние от пристани

Ответ. на 5 км отъехал рыболов

Answer 2

Problem Analysis

We are given the following information: - The fisherman traveled a certain distance upstream from the dock in his boat. - He then dropped anchor and fished for 2 hours. - After that, he returned back to the dock in 5 hours. - The speed of the river's current is 4 km/h. - The speed of the boat is 6 km/h.

We need to find the distance from the dock where the fisherman dropped anchor.

Solution

Let's assume the distance from the dock where the fisherman dropped anchor is x km.

When the fisherman traveled upstream, the effective speed of the boat is the difference between the speed of the boat and the speed of the current. So, the effective speed is 6 km/h - 4 km/h = 2 km/h.

The time taken to travel upstream is given by the equation: time = distance / speed. Therefore, the time taken to travel upstream is x / 2 hours.

After fishing for 2 hours, the fisherman returns back to the dock. This time, the effective speed of the boat is the sum of the speed of the boat and the speed of the current. So, the effective speed is 6 km/h + 4 km/h = 10 km/h.

The time taken to travel downstream is given by the equation: time = distance / speed. Therefore, the time taken to travel downstream is x / 10 hours.

The total time taken for the round trip is 5 hours. So, the equation becomes: (x / 2) + 2 + (x / 10) = 5.

Simplifying the equation: - Multiply through by 10 to eliminate the denominators: 5x + 20 + x = 50. - Combine like terms: 6x + 20 = 50. - Subtract 20 from both sides: 6x = 30. - Divide both sides by 6: x = 5.

Therefore, the fisherman dropped anchor at a distance of 5 km from the dock.

Answer

The fisherman dropped anchor at a distance of 5 km from the dock.