[tex]\text{Notam cu x pretul initial.}\\
x-\dfrac{10}{100}\cdot x-\dfrac{12}{100}\left(x-\dfrac{10}{100}\cdot x\right)=57,42\\
x-\dfrac{x}{10}-\dfrac{3}{25}\left(x-\dfrac{x}{10}\right)=57,42\\
\dfrac{9x}{10}-\dfrac{3}{25}\cdot \dfrac{9x}{10}=57,42\\
\\
\dfrac{9x}{10}-\dfrac{27x}{250}=57,42|\cdot 250\\
\\
225x-27x=14355\\
198x=14355\Rightarrow \boxed{x=72,5\ lei}\\
R:\text{Pretul initial a fost de 72,5 lei.}[/tex]