Question

Paulina swims 5 miles down a creek with a current for 2 hours. It takes her 4 hours to swim the same 5 miles back to her original destination against the same current.

what is her speed and the speed of the current?

Answer 1

1.885 mi/hr, 0.635 mi/hr

Explanation:

Let the speed of the current = v miles/hour.

Let the swimming speed of Paulina in still water be = u miles/hour

Pulina's speed down the creek = u+v

Paulina's speed up the creek = u - v

So for the swim downstream: 5/(u+v) = 2 => u+v = 2.5

for the upstream: 5/(u-v) = 4 => u-v = 1.25

=> u = 1.885 mi/hr

=> v = 0.635 mi/hr