You can
put this solution on YOUR website! Assume the rowing speed is Vr and the current speed is Vw.
We have the downstream speed: Vr + Vw = 55/5 = 11 ...(1)
and the upstream speed Vr - Vw = 55/11 = 5 ...(2)
Hence, Vr = (11+5)/2 = 8 miles/hr and Vw = (11-5)/2 = 3 miles/hr
Kenny
PS: Usually, I don't answer such kind of simple question and similar
questions appeared thousand times here.
To avoid that you got terrible long solutions so I showed something
that I learned when I was in elementary school and hope you don't
bother with this kinds of question any more.