Question:
$\frac{0.2 x+5}{3.5 x-3}=\frac{2}{5}$
Solution:
Given, $\frac{0.2 x+5}{3.5 x-3}=\frac{2}{5}$
$\Rightarrow$ $5(0.2 x+5)=2(3.5 x-3)$ [by cross-multiplication]
$\Rightarrow \quad$ $x+25=7 x-6$
$\Rightarrow$ $x-7 x=-6-25 \quad$ [transposing $7 x$ to LHS and 25 to RHS]
$\Rightarrow$ $-6 x=-31$
$\Rightarrow$ $\frac{-6 x}{-6}=\frac{-31}{-6}$ [dividing both sides by $-6$ ]
$\therefore$ $x=\frac{31}{6}$