The boat’s own speed is 8.5 km / h, the speed of the river is 1.5 km / h. The distance between the marinas is 17.5 km.

| May 3, 2021 | education

The boat’s own speed is 8.5 km / h, the speed of the river is 1.5 km / h. The distance between the marinas is 17.5 km. How long will it take for the boat to sail this distance if it floats along the river?

Let’s calculate the speed of the boat as it floats downstream of the river. Let’s add the boat’s own speed in still water – 8.5 kilometers per hour and the speed of the river flow – 1.5 kilometers per hour:

8.5 + 1.5 = 10 kilometers per hour.

The speed of the boat along the river is 10 kilometers per hour.

Let’s calculate the time it takes for the boat to sail from the pier to the pier. We divide the distance – 17.5 kilometers by the speed of the boat along the river – 10 kilometers per hour:

17.5: 10 = 1.75 hours = 1 hour 45 minutes.

Answer: the boat will sail in 1 hour and 45 minutes.



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