In a countercurrent stripping operation using pure steam, the mole ratio of a solute in the liquid stream is reduced from $0.25$ to $0.05$. The liquid feed flowrate, on a solute-free basis, is $3$ mol/$s$. The equilibrium line for the system is given in the below figure below.
The MINIMUM flowrate of pure steam for this process, rounded to $1$ decimal place, is _____________ mol/$s$.