[tex]1~bluza~.......~1,75~m~matase
12~bluze~........~x
-----------------------------------
Sunt~marimi~direct~proportionale
\frac{1}{12} = \frac{1,75}{x} = \ \textgreater \ x = \frac{12 \cdot 1,75}{1} = \ \textgreater \ x = \frac{21}{1}
= \ \textgreater \ \boxed{21 ~m~matase }[/tex]
