Answer:
4 miles per hour
Step-by-step explanation:
The given relations allow us to write two equations.
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The downstream speed is the sum of the canoe speed and the stream speed:
6 = c + s
The upstream speed is the difference of the canoe speed and the stream speed:
2 = c - s
Adding these two equations, we get ...
8 = 2c
4 = c . . . . . divide by 2
The canoe speed in still water is 4 miles per hour.
