[tex]9\frac{1}{2}=\frac{19}{2} ft -cedar \\ \\ 5\frac{2}{3}=\frac{17}{3}ft-redwood \\ \\ 4\frac{3}{4}=\frac{19}{4}ft-cedar \\ \\\\ \frac{19}{2}c...........\frac{17}{3}r \\ \\ \frac{19}{4}..............x \\ \\ x=\frac{ \frac{19}{4}*\frac{17}{3}}{\frac{19}{2}}= \frac{19}{4}*\frac{17}{3}*\frac{2}{19} \\ \\\boxed{ x= \frac{17}{6}ft \ -redwood}[/tex]