A motorboat travels 552 km in eight hours going upstream and 297 km in three hours going downstream. What is the rate of the boat in Stillwater and what is the rate of the current

Question

question.

Answer 1

Let "b" represent the rate of the boat in still water. Let "w" represent the rate of the water.

When the boat is traveling upstream, its rate will be (b - w) and when the boat is traveling downstream, its rate will be (b + w)

The rate upstream is 552/8 = 69 km/hr so b - w = 69

The rate downstream is 297/3 = 99 km/hr so b + w = 99

Add the equations together to eliminate the variable "w":

b - w = 69

b + w = 99

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2b = 168

b = 84

So the boat in still water goes 84 km/hr

Since b + w = 99, the 84 + w = 99 or w = 15 so the rate of the current is 15 km/hr