Question

Chan rows at a rate of 8 mph in still water. It takes him three hours to row upstream from his house to the park. He rows back home, and it takes him 2 hours. What is the speed of the current?

Answer 1

d = r * t

                               time                rate                       distance

Downstream:           2                   8 + c                     d = 2(8 + c)

Upstream:                3                   8 - c                      d = 3(8 - c)

Since the distance is the same, we can set the distance equations equal to each other and solve for c.

2(8 + c) = 3(8 - c)

16 + 2c = 24 - 3c

16 + 5c = 24

      5c = 8

        c = $\frac{8}{5}$

        c = 1.6

Answer: 1.6 mph