1. The problem statement, all variables and given/known data 2. Relevant equations 3. The attempt at a solution The problem here is that it looks like having 2 equilibrium stages requires the same flow ratio as one equilibrium stage, according to my calculations. This seems strange to me, so I am wondering if I am wrong. I also am not sure if it's asking the ratio relative to the raffinate from the first stage, or if it is a ratio of the inlet from the first stage to the raffinate of the second stage.