[tex]Voi~nota~pretul~initial~cu~x. \\ \\ In~urma~unei~reduceri~de~10 \%~din~pretul~initial, ~pretul~final~va~fi\\ \\~de~90 \%~din~pretul~initial. \\ \\ \frac{90}{100} \cdot x=27 \Rightarrow x= \frac{27 \cdot 100}{90}=30~(lei). \\ \\ Pretul~initial:~30~lei. [/tex]