Răspuns :
[tex]\displaystyle \\ \texttt{Numerele impare mai mici decat 9 sunt: } \{1;~3;~5;~7\} \\ \\ n = 2 \times C_4^2 = 2 \times \frac{4 \times 3}{1\times 2} = 2\times6 = \boxed{12~numere} \\ \\ sau: \\ \\ n = A_4^2 = 4 \times 3 = \boxed{12~numere} [/tex]
