in still water, a speed boat travels 5 times faster than the current of the river. If the speed boat can travel 48 miles upstream and then back in 5 hours, find the rate of the current.

Answer 1

If the current speed is c, then the boat's speed is 5c.

Since time = distance/speed,

48/(5c-c) + 48/(5c+c) = 5
12/c + 8/c = 5
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