On a canoe trip Rita paddled upstream against the current at

On a canoe trip, Rita paddled upstream (against the current) at an average speed of 2mi/h relative to the riverbank. On the return trip downstream (with the current), her average speed was 3 mi/h. Find Rita\'s paddling sp eed in still water and the speed of the river\'s current.

Solution

Upstream DATA:
rate = 2 mph
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Downstream DATA:
rate = 3 mph
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Let P be paddling speed and c be current speed:
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Equations:
p + c = 3 mph
p - c = 2 mph
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Add to get:
2p = 5 mph
p = 2.5 mph (paddling speed)
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Substitute to solve for \"c\":
2.5 + c = 3
c = 0.5 mph (speed of the current)