Part of Dr$.$ Ritchey's work in her previous job involved boiling and condensing hydrocarbon mixtures. In one of her experiments, she used a binary mixture of n$-$pentane $($density $39\mathrm{.}1lb\frac{m}{f}{t}^3)$ and p$-$xylene $($density $53\mathrm{.}8lb\frac{m}{f}{t}^3).$ One outlet stream of her condenser was measured to have a flow rate of $50ft\frac{3}{m}in$ and a concentration of $\frac{30}{70}n-$pentane$/\frac{?}{p}-$xylene by volume. The other outlet stream was measured to have a flow rate of $25f\frac{t^3}{m}in$ and a concentration of $\frac{50}{50}n-$pentane$/$p$-$xylene by volume. If the system operates at steady state and the only inlet to her condenser has a flow rate of $75f\frac{t^3}{m}in,$ what is the inlet concentration of $n-$pentane in $\%$ by volume? $($Your answer should be between $0$ and $100.$ Round your answer to $1$ decimal place for entry into Canvas. Do not enter units. Example: $12\mathrm{.}3)$ Note: $\frac{30}{70}$ by volume means that $30\%$ of the volume is $n-$pentane and $70\%$ of the volume is $p$ xylene.