SOLUTION: The Jones family took a 12 mile canoe ride down the Indian River in two hours. After lunch, the return trip back up the river took six hours. Find the rate, in mph, of the canoe in

Their rate canoeing downstream was   = 6 miles per hour,

and this rate is the SUM  of the rate of the canoe  in still water and the rate of the current:

u + v = 6     (1)



Their rate upstream was   = 2 miles per hour,

and this rate is the DIFFERENCE  of the rate of the canoe  in still water and the rate of the current:

u - v = 2     (2)


Add equations (1) and (2). You will get


2u = 6 + 2 = 8,  which implies   u = 8/2 = 4 miles per hour is the rate of the canoe in still water.


Now substitute it into equation (1) to get


v = 6 - u = 6 - 4 = 2 miles per hour is the rate of the current.


ANSWER.  The rate of the canoe in still water is 4 miles per hour.

         The rate of the current is 2 miles per hour.