\(\frac{17-x}{1+\frac{1}{2}}=1-\frac{1}{12}.x=>\frac{17-x}{\frac{3}{2}}=1-\frac{1}{12}.x=>\frac{\left(17-x\right).2}{3}=1-\frac{1}{12}.x\)
\(=>\left(17-x\right).2=\left(1-\frac{1}{12}.x\right).3=>34-2x=3-\frac{1}{4}x\)
\(=>34-2x-3+\frac{1}{4}x=0=>-\frac{7}{4}x+31=0=>-\frac{7}{4}x=-31=>x=\left(-31\right):\left(-\frac{7}{4}\right)=\frac{124}{7}\)