Calculating the Speed of the River Current for Rick's Kayaking Trip

Rick's Kayaking Adventure

Rick paddled up the river, spent the night camping, and then paddled back. He spent 8 hours paddling and the campground was 15 miles away. If Rick kayaked at a speed of 4 mph, what was the speed of the current (in mph)?

Final answer:

To find the speed of the river current, two equations representing Rick's time paddling upstream and downstream were formulated and solved to find that the speed of the current is 1 mph.

Explanation:

Calculating the Speed of the River Current

To determine the speed of the current, we would need to use the principle that the actual speed of a boat paddling upstream against a current is decreased by the speed of the current, while the speed downstream is increased by the speed of the current. Let's denote the speed of the current as c mph. When Rick paddles up the river against the current, his effective speed would be (4 - c) mph, and while going downstream with the current, his speed would be (4 + c) mph. Since the campground is 15 miles away, and he spent 8 hours paddling both ways, we can set up two equations to represent the time spent going each way:

  • Time upstream = Distance / Speed upstream
  • Time downstream = Distance / Speed downstream

We know that the sum of the two times is 8 hours (Time upstream + Time downstream = 8). By plugging in the distances and speeds, we get the following:

  • Time upstream = 15 / (4 - c)
  • Time downstream = 15 / (4 + c)

Adding both equations gives us 15 / (4 - c) + 15 / (4 + c) = 8. To find the value of c, we solve this equation.

After calculating, we find that the speed of the current c is 1 mph.

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