Question

In still water, a boat averages 12 miles per hour. It takes the same amount of time to travel 14 miles downstream, with the current, as it does 7 miles upstream, against the current. What is the rate of the waters current?

Answer 1

T is equal in both situations ... d = r X t   so d/r = t
c is rate of waters current

$\frac{14}{12+c} = \frac{7}{12-c}$
14(12 - c) = 7(12 + c)
2(12 - c) = 12 + c
24 - 2c = 12 + c
12 = 3c
4 = c     The rate of the waters current is 4 miles per hour.