71 + 65 x 4 = \(\frac{x+140}{x+260}\)
71 + 260 = \(\frac{x+140}{x+260}\)
331 = \(\frac{x+140}{x+260}\)
\(\Rightarrow x+140=331\left(x+260\right)\)
\(\Rightarrow x+140=331x+86060\)
\(\Rightarrow140-86060=331x-x\)
\(\Rightarrow330x=85920\)
\(\Rightarrow x=\frac{2864}{11}\)